Ongoing problems with E-Mail login

[Frdnspnzr]

The E-Mail login was broken multiple times for multiple users. Unfortunately I can't even pinpoint what exactly goes wrong right now.

• Verification tokens are never deleted from the database, even though new ones are created and the old ones get invalidated. I'm not sure if this is expected behaviour. I also can't delete them manually as the database table does not have a primary key and my database provider does not support this.
• One user created their account from a mobile phone and could not log in using their computer even though multiple verification tokens were created. I do not know wether the login e-mails were even sent.
• One user could not log in to their account after creating it (using the same device to do both). No verficiation tokens were sent even though they were created in the database. Providing the user with a login link using the tokens from the database still did not allow them to log in.

[Frdnspnzr]

It still happens from time to time in preview deployments. It seems to fix the issue when deleting old verification tokens or sessions from the database.

[Frdnspnzr]

I have now tried several providers locally and in preview and it still doesn't work.

This seems to explain it pretty well? That would explain it working occasionally: When the function finishes fast enough to send the email. It would also explain it working after database operations: This may add some additional overhead when re-establishing the database connection, thereby giving the function enough time to finish.

As next-auth supports overwriting the email sending functionality it may be worth to give the soltion in the StackOverflow thread a shot.

[Frdnspnzr]

After several hours of testing different email service providers I may have finally found one that works for me. It looks like nothing in the code needs to change and I can just plug in a faster SMTP server this way. I will keep this issue open for another while just to make sure there aren't any more problems.