These two error messages appear:
One or more newsletters have been blocked due to severe delivery error. Check and restart.
This is the second one in a red bar
Stopped by fatal error: SMTP Error: The following recipients failed: s………7@fremail.hu: Temporary local problem – please try later
I updated the plugin to version 8.9.9 this afternoon, and now this problem has arisen. There were no problems for weeks, and it can’t be related to the update, as it happened before noon.
The most annoying thing is that I am in the process of closing a campaign, and this was supposed to be the last letter, but unfortunately only 57% of them were sent.