While creating a user auth token and you click Create New Token, the process does not complete. Eventually the server shows a 504 gateway timeout error. Incorrect mail server settings can cause this problem.

Confirm that Matomo can send emails using the console command documented in Emails from Matomo are not being sent, how do I troubleshoot and solve the issue?

Follow the guide How do I send Matomo emails using SMTP server? to ensure the SMTP server settings are correct.

Previous FAQ: Why many of my visits have “0 Action” in Matomo and how do I fix this issue?