In case you have access to your device with the authenticator app but 2FA codes from it are not working, please follow instructions below. If you have lost access to your authenticator, please proceed to the following article.
What you can do if 2FA codes are not working.
1. Please make sure that date&time settings both on your phone and your computer are the same and precisely correct. Not only the time but time zone as well should be properly set up.
2. Also check time zone settings in your HitBTC account at your Settings page.
3. If you have many, pay attention to the authentication app you use to generate the code: it should be the app which you used to set up 2FA on HitBTC.
In case the problem persists, try to log in with your backup code which should have been saved during 2FA set up.
Then disable your 2FA on the Settings page and enable it with another app.