Resolve "Error during login"

I cannot reproduce this specific issue, but when I checked the stacktrace it points to: https://github.com/jazzband/django-two-factor-auth/pull/402/files#diff-47e9cf2bbbe1952606db449365a94f378e479389cc4c53d52310ceed0605646dL163

I believe this pull request was included in version 1.13.1 and should fix the problem.

Closes #486 (closed)