diff --git a/examples/__tests__/test-status-deserialize-class.ava.js b/examples/__tests__/test-status-deserialize-class.ava.js
index f52d92d24..43bb69748 100644
--- a/examples/__tests__/test-status-deserialize-class.ava.js
+++ b/examples/__tests__/test-status-deserialize-class.ava.js
@@ -149,21 +149,3 @@ test("Ali set_extra_record without schema defined then gets", async (t) => {
   const recordWithoutSchemaDefined = await statusMessage.view("get_extra_record", { account_id: ali.accountId });
   t.is(recordWithoutSchemaDefined, "Hello world!");
 });
-
-test("View get_subtype_of_efficient_recordes", async (t) => {
-  const { statusMessage } = t.context.accounts;
-
-  t.is(
-      await statusMessage.view("get_subtype_of_efficient_recordes", { }),
-      'string'
-  );
-});
-
-test("View get_subtype_of_nested_efficient_recordes", async (t) => {
-  const { statusMessage } = t.context.accounts;
-
-  t.is(
-      JSON.stringify(await statusMessage.view("get_subtype_of_nested_efficient_recordes", { })),
-      '{"collection":{"value":"string"}}'
-  );
-});
\ No newline at end of file
diff --git a/packages/near-sdk-js/lib/collections/subtype.js b/packages/near-sdk-js/lib/collections/subtype.js
index 0b4ee206f..24d31f65b 100644
--- a/packages/near-sdk-js/lib/collections/subtype.js
+++ b/packages/near-sdk-js/lib/collections/subtype.js
@@ -7,19 +7,17 @@ export class SubType {
             options = {};
         }
         const subtype = this.subtype();
-        if (options.reconstructor == undefined &&
-            subtype != undefined) {
+        if (options.reconstructor == undefined && subtype != undefined) {
             if (
             // eslint-disable-next-line no-prototype-builtins
             subtype.hasOwnProperty("class") &&
-                typeof subtype.class.reconstructor === "function") {
-                // { collection: {reconstructor: LookupMap.reconstruct, value: 'string'}}
+                typeof subtype.class.reconstruct === "function") {
                 // eslint-disable-next-line @typescript-eslint/ban-ts-comment
                 // @ts-ignore
-                options.reconstructor = subtype.class.reconstructor;
+                options.reconstructor = subtype.class.reconstruct;
             }
-            else if (subtype.reconstructor === "function") {
-                options.reconstructor = subtype.reconstructor;
+            else if (typeof subtype.reconstruct === "function") {
+                options.reconstructor = subtype.reconstruct;
             }
         }
         return options;
diff --git a/packages/near-sdk-js/lib/utils.js b/packages/near-sdk-js/lib/utils.js
index b0cfe8b00..c6da00bc4 100644
--- a/packages/near-sdk-js/lib/utils.js
+++ b/packages/near-sdk-js/lib/utils.js
@@ -52,14 +52,14 @@ export function getValueWithOptions(subDatatype, value, options = {
         const collection = options.reconstructor(deserialized);
         if (subDatatype !== undefined &&
             // eslint-disable-next-line no-prototype-builtins
-            subDatatype.hasOwnProperty("collection") &&
+            subDatatype.hasOwnProperty("class") &&
             // eslint-disable-next-line no-prototype-builtins
-            subDatatype["collection"].hasOwnProperty("value")) {
+            subDatatype["class"].hasOwnProperty("value")) {
             // eslint-disable-next-line @typescript-eslint/ban-ts-comment
             // @ts-ignore
             collection.subtype = function () {
-                // example: { collection: {reconstructor: LookupMap.reconstruct, value: 'string'}}
-                return subDatatype["collection"]["value"];
+                // example: {class: UnorderedMap, value: UnorderedMap}
+                return subDatatype["class"]["value"];
             };
         }
         return collection;
@@ -143,7 +143,9 @@ export function deserialize(valueToDeserialize) {
     });
 }
 export function decodeObj2class(class_instance, obj) {
-    if (typeof obj != "object" || typeof obj === "bigint" || obj instanceof Date ||
+    if (typeof obj != "object" ||
+        typeof obj === "bigint" ||
+        obj instanceof Date ||
         class_instance.constructor.schema === undefined) {
         return obj;
     }
@@ -180,15 +182,17 @@ export function decodeObj2class(class_instance, obj) {
                 // eslint-disable-next-line no-prototype-builtins
             }
             else if (ty !== undefined && ty.hasOwnProperty("class")) {
-                // nested_lookup_recordes: {collection: {reconstructor: UnorderedMap.reconstruct, value: { collection: {reconstructor: LookupMap.reconstruct, value: 'string'}}}},
-                // {collection: {reconstructor:
+                // => nested_lookup_recordes:  {class: UnorderedMap, value: {class: LookupMap }},
                 class_instance[key] = ty["class"].reconstruct(obj[key]);
-                const subtype_value = ty["value"];
-                class_instance[key].subtype = function () {
-                    // example: { collection: {reconstructor: LookupMap.reconstruct, value: 'string'}}
-                    // example: UnorderedMap
-                    return subtype_value;
-                };
+                // eslint-disable-next-line no-prototype-builtins
+                if (ty.hasOwnProperty("value")) {
+                    const subtype_value = ty["value"];
+                    class_instance[key].subtype = function () {
+                        // example: { collection: {reconstructor: LookupMap.reconstruct, value: 'string'}}
+                        // example: UnorderedMap or {class: UnorderedMap, value: 'string'}
+                        return subtype_value;
+                    };
+                }
             }
             else if (ty !== undefined && typeof ty.reconstruct === "function") {
                 class_instance[key] = ty.reconstruct(obj[key]);
diff --git a/packages/near-sdk-js/src/collections/subtype.ts b/packages/near-sdk-js/src/collections/subtype.ts
index 07cd5944b..86f281bbc 100644
--- a/packages/near-sdk-js/src/collections/subtype.ts
+++ b/packages/near-sdk-js/src/collections/subtype.ts
@@ -12,20 +12,17 @@ export abstract class SubType<DataType> {
       options = {};
     }
     const subtype = this.subtype();
-    if (
-      options.reconstructor == undefined &&
-      subtype != undefined
-    ) {
+    if (options.reconstructor == undefined && subtype != undefined) {
       if (
-          // eslint-disable-next-line no-prototype-builtins
-          subtype.hasOwnProperty("class") &&
-          typeof subtype.class.reconstructor === "function") {
-        // { collection: {reconstructor: LookupMap.reconstruct, value: 'string'}}
+        // eslint-disable-next-line no-prototype-builtins
+        subtype.hasOwnProperty("class") &&
+        typeof subtype.class.reconstruct === "function"
+      ) {
         // eslint-disable-next-line @typescript-eslint/ban-ts-comment
         // @ts-ignore
-        options.reconstructor = subtype.class.reconstructor;
-      } else if (subtype.reconstructor === "function") {
-        options.reconstructor = subtype.reconstructor;
+        options.reconstructor = subtype.class.reconstruct;
+      } else if (typeof subtype.reconstruct === "function") {
+        options.reconstructor = subtype.reconstruct;
       }
     }
     return options;
diff --git a/packages/near-sdk-js/src/utils.ts b/packages/near-sdk-js/src/utils.ts
index 2e3519fcf..b9abfa314 100644
--- a/packages/near-sdk-js/src/utils.ts
+++ b/packages/near-sdk-js/src/utils.ts
@@ -94,15 +94,15 @@ export function getValueWithOptions<DataType>(
     if (
       subDatatype !== undefined &&
       // eslint-disable-next-line no-prototype-builtins
-      subDatatype.hasOwnProperty("collection") &&
+      subDatatype.hasOwnProperty("class") &&
       // eslint-disable-next-line no-prototype-builtins
-      subDatatype["collection"].hasOwnProperty("value")
+      subDatatype["class"].hasOwnProperty("value")
     ) {
       // eslint-disable-next-line @typescript-eslint/ban-ts-comment
       // @ts-ignore
       collection.subtype = function () {
-        // example: { collection: {reconstructor: LookupMap.reconstruct, value: 'string'}}
-        return subDatatype["collection"]["value"];
+        // example: {class: UnorderedMap, value: UnorderedMap}
+        return subDatatype["class"]["value"];
       };
     }
     return collection;
@@ -208,7 +208,9 @@ export function deserialize(valueToDeserialize: Uint8Array): unknown {
 
 export function decodeObj2class(class_instance, obj) {
   if (
-      typeof obj != "object" || typeof obj === "bigint" || obj instanceof Date ||
+    typeof obj != "object" ||
+    typeof obj === "bigint" ||
+    obj instanceof Date ||
     class_instance.constructor.schema === undefined
   ) {
     return obj;
@@ -247,15 +249,17 @@ export function decodeObj2class(class_instance, obj) {
         }
         // eslint-disable-next-line no-prototype-builtins
       } else if (ty !== undefined && ty.hasOwnProperty("class")) {
-        // nested_lookup_recordes: {collection: {reconstructor: UnorderedMap.reconstruct, value: { collection: {reconstructor: LookupMap.reconstruct, value: 'string'}}}},
-        // {collection: {reconstructor:
+        // => nested_lookup_recordes:  {class: UnorderedMap, value: {class: LookupMap }},
         class_instance[key] = ty["class"].reconstruct(obj[key]);
-        const subtype_value = ty["value"];
-        class_instance[key].subtype = function () {
-          // example: { collection: {reconstructor: LookupMap.reconstruct, value: 'string'}}
-          // example: UnorderedMap
-          return subtype_value;
-        };
+        // eslint-disable-next-line no-prototype-builtins
+        if (ty.hasOwnProperty("value")) {
+          const subtype_value = ty["value"];
+          class_instance[key].subtype = function () {
+            // example: { collection: {reconstructor: LookupMap.reconstruct, value: 'string'}}
+            // example: UnorderedMap or {class: UnorderedMap, value: 'string'}
+            return subtype_value;
+          };
+        }
       } else if (ty !== undefined && typeof ty.reconstruct === "function") {
         class_instance[key] = ty.reconstruct(obj[key]);
       } else {