How to Fix-(Your DNS PTR record does not match your forward DNS en

Only one company we does with has this problem. When I send a message I get
this return message

The e-mail system was unable to deliver the message, but did not report a
specific reason. Check the address and try again. If it still fails,
contact your system administrator.
<mail.US.com #4.0.0 smtp;452 Too many recipients received this
hour. Possible causes might be invalid rDNS (Your DNS PTR record does not
match your forward DNS entry).>

This happens about 50% of the time. Is the problem on our end or theres?
If it is ours, how do we fix it? The only think I can think of is all
incoming mail goes to XX.XX.XX.11 and all outbound mail comes from
XX.XX.XX.10 The one is to access the server from the outside world and the
other is the IP is what I see if go to an IP site and check it.

 

Check your domain on www.dnsreport.com and see what it shows about your PTR
record.

 

It says PASS

But like I said before, would the problem have anything to do with a
diffrent outbound ip the my inbound ip? Thats all i could think of. not
much of an IT guy here, just sort of tossed into the roll. I try to bump my
way though. So any more insight would be great.