Have a catchall / default email setup at the hosts, and some auto responders there as well. All has worked perfectly for about 14 years with no issues, noticed a few days ago, that the last email received from there was last April, and usually there's at least 2/3 a week, (it's not the main business, so it wasn't top on the radar).
I've tested it umpteen times, and sending to a particular email address is fine, but no-one seems to receive it???
Any help much appreciated.