Emails suddenly stopped being sent despite test email working!

Hi, from this morning, suddenly discourse has stopped sending emails. The emails are not recorded in the email logs at all. when i send a test email, it works perfectly but other discourse emails are not sent and do not show up on that page either.
i checked the email with mail-tester and everything is perfect there, also double checked all the configs.
in discourse log i see some errors with [db6505] Can’t verify CSRF token authenticity.

I searched and couldn’t find any relevant info, does anyone know what’s going on and how can i fix this ?
thanks!

This is another occurrence of Sidekiq hangs (on BotInput job?)