Authenticator transfer fails with Unknown Error on new phone

Hello,

I’m experiencing a bug when trying to transfer my Battle.net Mobile Authenticator to a new phone, and after contacting support with no solution, I was advised to post this issue here on the official forums.

Problem summary:
I can log in to my Battle.net account on the new phone without any issues. However, when I try to attach / link the Mobile Authenticator to the new device, the process always fails with an “Unknown Error”.

Steps where the error occurs:

  1. Install the Battle.net mobile app on the new phone.
  2. Log in successfully (login works fine).
  3. Start the process to add / restore the Mobile Authenticator.
  4. Enter:
  • Serial number
  • Restore code
  • Email address or phone number
  1. Press the confirmation button.

At this point, the process fails:

  • If I use my email address, I get an “Unknown Error” message.
  • If I use my phone number, I get a different popup, but the result is the same: the authenticator cannot be linked.

What I have already tried (as requested by support):

  • Reinstalled the Battle.net app multiple times
  • Cleared app cache and data
  • Unlinked / removed the authenticator from the old phone
  • Verified that the serial and restore codes are correct
  • Tried both email and phone number
  • Restarted the device and tested on a stable network

Despite all of this, the error persists every time.

Additional notes:

  • The old authenticator was working correctly before changing phones.
  • Login without the authenticator works fine on the new device.
  • The issue only happens during the authenticator transfer/linking step.

This seems to be either a backend or app-related issue, as the same behavior happens consistently regardless of the input method.

Has anyone experienced this issue recently, or is Blizzard aware of a current problem with authenticator transfers on mobile?

Thanks in advance for any help or clarification.

Did you find a solution to your problem? I’m experiencing the same issue. I do have all necessary credentials but it won’t let me transfer. The only thing I haven’t tried yet is unlinking the authenticator first, but the app warns that might cause problems so I haven’t done it yet. Since I can login and use the authenticator on the old phone I’d rather not lock myself out. It’s just cumbersome to still be using the old phone just for this…