diff --git a/app/assets/javascripts/application/posts.js b/app/assets/javascripts/application/posts.js
index 71d26223..bee108d0 100644
--- a/app/assets/javascripts/application/posts.js
+++ b/app/assets/javascripts/application/posts.js
@@ -50,5 +50,11 @@ function addPost(group_id, membership_id, post_type_id) {
                 button.disabled = false
             });
         }
+        if(response.status == 403){
+            response.json().then(data => {
+                UIkit.notify({message: data.message, timeout: 3000, status: 'danger'})
+                button.disabled = false
+            })
+        }
     })
 }
diff --git a/app/controllers/posts_controller.rb b/app/controllers/posts_controller.rb
index 5f55c833..27003ed0 100644
--- a/app/controllers/posts_controller.rb
+++ b/app/controllers/posts_controller.rb
@@ -23,15 +23,23 @@ def create
     membership = Membership.find(params[:membership_id])
     post_type_id = params[:post_type_id].to_i
     authorize Post.new(membership: membership, post_type_id: post_type_id)
-
-    new_post = CreatePost.call(group, membership, post_type_id)
+    begin
+      new_post = CreatePost.call(group, membership, post_type_id)
+    rescue CreatePost::PostAlreadyTaken
+      post_taken = true
+    end
     respond_to do |format|
       format.html do
-        return redirect_to group_path(group) if new_post.leader?
+        flash[:notice] = t('services.create_post.post_already_taken') if post_taken
+        return redirect_to group_path(group) if new_post&.leader?
+
+        redirect_to group_membership_posts_path(group, membership)
+      end
+      format.json do
+        return render status: :forbidden, json: { message: t('services.create_post.post_already_taken') } if post_taken
 
-        redirect_back fallback_location: group_path(group)
+        render json: { post_id: new_post.id }
       end
-      format.json { render json: { post_id: new_post.id } }
     end
   end
 
diff --git a/app/services/create_post.rb b/app/services/create_post.rb
index e55c7e78..ce4eeedc 100644
--- a/app/services/create_post.rb
+++ b/app/services/create_post.rb
@@ -1,5 +1,6 @@
 class CreatePost
   class InvalidPostType < StandardError; end
+  class PostAlreadyTaken < StandardError; end
 
   def self.call(group, membership, post_type_id)
     raise InvalidPostType unless group.has_post_type?(post_type_id)
@@ -9,6 +10,9 @@ def self.call(group, membership, post_type_id)
         remove_leader(group)
         remove_past_leader_post(membership)
       end
+      if post_type_id == PostType::FINANCIAL_OFFICER_POST_ID
+        raise PostAlreadyTaken unless financial_officer_count_for(group).zero?
+      end
       Post.create(membership_id: membership.id, post_type_id: post_type_id)
     end
   end
@@ -21,4 +25,10 @@ def self.remove_leader(group)
   def self.remove_past_leader_post(membership)
     Post.where(membership_id: membership.id, post_type_id: PostType::PAST_LEADER_ID).destroy_all
   end
+
+  def self.financial_officer_count_for(group)
+    Post.where('memberships.group_id': group.id,
+               post_type_id: PostType::FINANCIAL_OFFICER_POST_ID)
+        .joins(:membership).count
+  end
 end
diff --git a/config/locales/hu.yml b/config/locales/hu.yml
index fa42ea89..0c3c4b65 100644
--- a/config/locales/hu.yml
+++ b/config/locales/hu.yml
@@ -91,3 +91,6 @@ hu:
       next: "Következő &raquo;"
       last: "Utolsó"
       truncate: "..."
+  services:
+    create_post:
+      post_already_taken: 'Ezt a posztot már kiosztottad valakinek! Vissza kell venned a jelenlegi posztot, hogy újra kiosztható legyen.'
diff --git a/db/migrate/20220520160742_remove_financial_officers_if_more_then_one.rb b/db/migrate/20220520160742_remove_financial_officers_if_more_then_one.rb
new file mode 100644
index 00000000..7e8d77c8
--- /dev/null
+++ b/db/migrate/20220520160742_remove_financial_officers_if_more_then_one.rb
@@ -0,0 +1,17 @@
+class RemoveFinancialOfficersIfMoreThenOne < ActiveRecord::Migration[6.0]
+  def up
+    groups_with_fo_count = Group.joins(memberships: :posts)
+                                .where('posts.post_type_id': PostType::FINANCIAL_OFFICER_POST_ID)
+                                .group('memberships.group_id').count('groups.id')
+    group_ids_with_more_fo = groups_with_fo_count.select { |k, v| v > 1 }.keys
+    groups_with_more_fo = Group.where(id: group_ids_with_more_fo)
+    groups_with_more_fo.each do |group|
+      fo_posts = Post.where('memberships.group_id': group.id,
+                            post_type_id: PostType::FINANCIAL_OFFICER_POST_ID)
+      .joins(:membership).order('posts.id': :asc)
+      fo_posts[0..-2].each { |post| post.destroy! }
+    end
+  end
+
+  def down;end
+end
diff --git a/db/structure.sql b/db/structure.sql
index b69be919..d07c4c68 100644
--- a/db/structure.sql
+++ b/db/structure.sql
@@ -1527,6 +1527,7 @@ INSERT INTO "schema_migrations" (version) VALUES
 ('20200722173131'),
 ('20201223070757'),
 ('20210307164901'),
-('20210905120558');
+('20210905120558'),
+('20220520160742');
 
 
diff --git a/spec/rails_helper.rb b/spec/rails_helper.rb
index bfe8819d..1e471f53 100644
--- a/spec/rails_helper.rb
+++ b/spec/rails_helper.rb
@@ -49,6 +49,7 @@
 
   config.before(:suite) do
     FactoryBot.create(:post_type_leader)
+    FactoryBot.create(:post_type_financial_officer)
     FactoryBot.create(:post_type_newbie)
     FactoryBot.create(:post_type_evaluation_helper)
     FactoryBot.create(:group_svie)
@@ -63,6 +64,7 @@
   end
 
   config.after(:suite) do
+    # Post.delete_all
     PostType.delete_all
     Group.delete_all
     User.delete_all
diff --git a/spec/requests/post_type_controller_spec.rb b/spec/requests/post_type_controller_spec.rb
index d86e971b..737b1fc2 100644
--- a/spec/requests/post_type_controller_spec.rb
+++ b/spec/requests/post_type_controller_spec.rb
@@ -55,6 +55,7 @@
       let(:group) { create(:group) }
       let(:user) { group.leader.user }
       before(:each) { login_as(user) }
+      # before(:each) { PostType.destroy(PostType::FINANCIAL_OFFICER_POST_ID) }
 
       it 'redirects back' do
         post "/groups/#{group.id}/post_types", params: {
diff --git a/spec/requests/posts_controller_spec_spec.rb b/spec/requests/posts_controller_spec_spec.rb
index 9e8d6beb..000a3471 100644
--- a/spec/requests/posts_controller_spec_spec.rb
+++ b/spec/requests/posts_controller_spec_spec.rb
@@ -15,6 +15,65 @@
         expect(response).to have_http_status :ok
         expect(response).to render_template :group_posts
       end
+
+      describe '#create' do
+        let(:membership) { group.memberships.first }
+        it 'creates a post and redirects' do
+          expect {
+            post "/groups/#{group.id}/memberships/#{membership.id}/posts",
+                 params: { post_type_id: PostType::FINANCIAL_OFFICER_POST_ID }
+          }.to change {
+            membership.posts.count
+          }.by(1)
+          expect(response).to redirect_to("/groups/#{group.id}/memberships/#{membership.id}/posts")
+        end
+
+        it 'when the post is for the leader it redirects to the group page' do
+          post "/groups/#{group.id}/memberships/#{membership.id}/posts",
+               params: { post_type_id: PostType::LEADER_POST_ID }
+
+          expect(response).to redirect_to("/groups/#{group.id}")
+        end
+
+        context 'when FINANCIAL_OFFICER is present' do
+          before(:each) do
+            CreatePost::call(group, membership, PostType::FINANCIAL_OFFICER_POST_ID)
+          end
+          it 'creating another FINANCIAL_OFFICER is not processed' do
+            expect {
+              post "/groups/#{group.id}/memberships/#{membership.id}/posts",
+                   params: { post_type_id: PostType::FINANCIAL_OFFICER_POST_ID }
+            }.to change {
+              membership.posts.count
+            }.by(0)
+
+            expect(flash[:notice]).to eql(I18n.t('services.create_post.post_already_taken'))
+            expect(response).to redirect_to("/groups/#{group.id}/memberships/#{membership.id}/posts")
+          end
+        end
+
+        context 'when format is json ' do
+          it 'sends back the post id' do
+            post "/groups/#{group.id}/memberships/#{membership.id}/posts.json",
+                 params: { post_type_id: PostType::FINANCIAL_OFFICER_POST_ID }
+
+            expect(response.body).to eql({ post_id: Post.last.id }.to_json)
+          end
+
+          context 'when FINANCIAL_OFFICER is present' do
+            before(:each) do
+              CreatePost::call(group, membership, PostType::FINANCIAL_OFFICER_POST_ID)
+            end
+            it 'creating another FINANCIAL_OFFICER is forbidden' do
+              post "/groups/#{group.id}/memberships/#{membership.id}/posts.json",
+                   params: { post_type_id: PostType::FINANCIAL_OFFICER_POST_ID }
+
+              expect(response).to have_http_status :forbidden
+              expect(response.body).to eql({ message: I18n.t('services.create_post.post_already_taken') }.to_json)
+            end
+          end
+        end
+      end
     end
   end
 end
diff --git a/test/factories/post_types.rb b/test/factories/post_types.rb
index 6222f93c..196eb7a1 100644
--- a/test/factories/post_types.rb
+++ b/test/factories/post_types.rb
@@ -7,7 +7,15 @@
     sequence(:id, 150)
   end
 
-  factory :post_type_leader, parent: :post_type do
+  factory :common_post_type, parent: :post_type do
+    group { nil }
+  end
+  factory :post_type_financial_officer, parent: :common_post_type do
+    id { PostType::FINANCIAL_OFFICER_POST_ID }
+    name { 'Gazdasagis' }
+  end
+
+  factory :post_type_leader, parent: :common_post_type do
     id { PostType::LEADER_POST_ID }
     name { 'Korvezeto' }
   end
@@ -17,20 +25,19 @@
     name { 'Feldolgozas alatt' }
   end
 
-  factory :post_type_pek_admin, parent: :post_type do
+  factory :post_type_pek_admin, parent: :common_post_type do
     group { Group.kirdev }
     id { PostType::PEK_ADMIN_ID }
     name { 'PeK admin' }
   end
 
-  factory :post_type_new_member, parent: :post_type do
+  factory :post_type_new_member, parent: :common_post_type do
     id { PostType::NEW_MEMBER_ID }
     name { 'Ujonc' }
   end
 
-  factory :post_type_evaluation_helper, parent: :post_type do
+  factory :post_type_evaluation_helper, parent: :common_post_type do
     id { PostType::EVALUATION_HELPER_ID }
-    group { nil }
     name { 'Pontozó' }
   end
 end