The email notification for a private message is delayed by several hours

[jsx]

Hi. After receiving a private message, the email notification about it arrives several hours later. The forum is running on SMF 2.1.6 after being upgraded from 2.1.4

[CRM 114]

There is a bug in 2.1.6 with sending mails/mail queue.

Look here:
https://www.simplemachines.org/community/index.php?topic=592099.0
https://www.simplemachines.org/community/index.php?topic=592094.0

[jsx]

Thank you for the message. The solution provided by @jdarwood007 fixed this bug.

https://github.com/SimpleMachines/SMF/issues/8712#issuecomment-3023814551