The code that gets sent to your phone by HMRC or the code shown in your authenticator app, is NOT the code you specify in Easy MTD when connecting Easy MTD with HMRC.
The code HMRC send to your phone or the code shown in your authenticator app is used to confirm it is you that is signing in to the Government Gateway. The code is used on the HMRC web page to authenticate the sign-in process and enable you to continue with the connection process.
At the end of the connection process a 32 character code is shown. Click the Copy button next to this code, go back to Easy MTD and click the Paste Code button. Now click the Connect button.
If you continue to experience problems connecting Easy MTD with HMRC, refer to the following knowledge base article: