Please delete the WTF folder in the World of Warcraft directory. After deletion, all game settings and plug-in settings will be restored to the default. If you don't want to delete it, please use Notepad to open the WTF-Config.wtf file, find the set accountName "Game Account", and change it to your account to facilitate login.
Set accountName "Fill in your account in double quotation marks" to exit saving.