Two Factor Authentication (2FA) is a great way for adding an extra layer of security to your account. However, if you lose your authentication app then things get a little tricky.
Use a Backup Code
When you switched 2FA on, you were asked to save some Backup Codes to a safe but different location to the authentication app.
You can use one of these Backup Codes as the authentication code when signing in instead of using a code generated from your authentication app.
You can then sign in, switch off 2FA and then decide if you want to switch it back on again once you have access to a new authentication app.
What if you don't have your Backup Codes?
Well...it gets even trickier.
You'll need to contact your Training Provider for assistance.