I recently traded in my old phone for a new one, but I left behind the Authenticator app. Now, I'm finding myself logged out of various apps and trying to manually access them using alternative login methods. I want to disconnect the old Authenticator and set up a new one, but I'm having trouble. When I try to remove the old Authenticator, I'm asked to enter the code that's being sent to it, but I no longer have access to that device. It's been over a month, and I really need assistance with this! By the way, I'm using Google Authenticator on my iPhone.
5 Answers
I thought switching would help as well, but I lost access to several accounts and my secondary eSIM got canceled too! It’s frustrating how these things happen without proper backups.
The code you're trying to enter isn't sent to the Authenticator; it's generated based on a secret that you should have saved during setup. Without that, you'll need to use any recovery codes provided when you initially set up 2FA for the services you're trying to access.
Unfortunately, when you trade in your phone without backing up or transferring your Authenticator codes, it can get pretty tricky. These apps are designed to be secure, so getting around that security is difficult for a reason. If you didn't save your codes to your Google account beforehand, you're likely going to have to reach out to customer support for each app you were using 2FA with.
I had a similar issue! I switched to Microsoft Authenticator since they auto-fix issues with phone upgrades. With Google, it’s a hassle if you didn't set it up properly before losing access. I learned that you need to install the app on your new phone and activate it with the old one before wiping it. It’s a mess, honestly.
If your old phone is gone, you might run into some challenges. You can check if your codes are backed up in your Google account by logging into your account on your new phone. If you're really stuck, consider using any backup codes you might have to disable 2FA and then set it up again fresh with the new device.

I thought the sync would take care of everything. The Authenticator app just opened to a blank screen on the new phone after I got home!