We are using our mailgun account to send SMTP email from service desk. All mail going out has a terrible FROM/REPLY address of
support=mydomain.com@mailgun.mydomain.com
Instead of support@mydomain.com
So if anyone replies to an email sent from service desk it of course bounces.
I use this mailgun account with my own scripts and apps constantly and simply force a FROM and REPLY-TO address of support@mydomain.com and it all works great.
What is causing this issue?