Steps to replicate the issue (include links if applicable):
I tried today to access to PAWS with my bot account Löwenbot (Spanish Wikipedia) but I received next Error message:

NoUsernameError(f'Failed {msg}')
pywikibot.exceptions.NoUsernameError: Failed OAuth authentication for wikipedia:es: The authorization headers in your request are not valid: No approved grant was found for that authorization token.
CRITICAL: Exiting due to uncaught exception NoUsernameError: Failed OAuth authentication for wikipedia:es: The authorization headers in your request are not valid: No approved grant was found forthat authorization token.

But if I access with my normal user account Leonprimer, it runs normally.

What should have happened instead?: Normal running with my Bot account

Software version (skip for WMF-hosted wikis like Wikipedia): PAWS

Other information (browser name/version, screenshots, etc.): I created the same Report at https://phabricator.wikimedia.org/T338080, I'm sorry about double Report, but I'm new here and I don't know where is the correct place to report it. If there's a problem with that, please erease the othe one Report.