diff --git a/app.ts b/app.ts
index f34d15a..b16f878 100644
--- a/app.ts
+++ b/app.ts
@@ -1,6 +1,6 @@
 import { App } from 'homey' // eslint-disable-line import/no-extraneous-dependencies
 import axios from 'axios'
-import withAPI, { getAPIErrorMessage } from './mixins/withAPI'
+import withAPI, { getErrorMessage } from './mixins/withAPI'
 import type {
   LoginCredentials,
   LoginData,
@@ -11,16 +11,6 @@ import type {
 
 axios.defaults.baseURL = 'https://www.ariston-net.remotethermo.com/api/v2'
 
-function getErrorMessage(error: unknown): string {
-  let errorMessage = String(error)
-  if (axios.isAxiosError(error)) {
-    errorMessage = getAPIErrorMessage(error)
-  } else if (error instanceof Error) {
-    errorMessage = error.message
-  }
-  return errorMessage
-}
-
 export = class AristonApp extends withAPI(App) {
   #loginTimeout!: NodeJS.Timeout
 
diff --git a/mixins/withAPI.ts b/mixins/withAPI.ts
index b1f8919..8b49847 100644
--- a/mixins/withAPI.ts
+++ b/mixins/withAPI.ts
@@ -18,6 +18,16 @@ export function getAPIErrorMessage(error: AxiosError): string {
   return error.message
 }
 
+export function getErrorMessage(error: unknown): string {
+  let errorMessage = String(error)
+  if (axios.isAxiosError(error)) {
+    errorMessage = getAPIErrorMessage(error)
+  } else if (error instanceof Error) {
+    errorMessage = error.message
+  }
+  return errorMessage
+}
+
 export default function withAPI<T extends HomeyClass>(base: T): APIClass & T {
   return class extends base {
     public api: AxiosInstance