https://eu.battle.net/support/en/help/product/services/974/977/solution
This seems to fit your issue.
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https://eu.battle.net/support/en/help/product/services/974/977/solution
This seems to fit your issue.
If you have a phone number on the account, you can do an SMS reset. If not, I guess it's "open a ticket with a throwaway" time.
I’d create a new account and then raise a support ticket that way for your old account.
Are you not able to replace the battery in them?
I tried but either age or removing the battery caused it to desynchronize. I got it right before Wrath of the Lich King, so it had a good run.