PTR Record Setup - Still an Issue

Comcast setup a PTR record for me, which I tested via dnstools.com; however when I email a comcast.net account, it still believes no PTR is setup. Any help will be appreciated on what to look for next.

   ----- Transcript of session follows -----
... while talking to mx2.comcast.net.:
<<< 554 resimta-ch2-01v.sys.comcast.net comcast 2601:283:4201:6300:5054:ff:fe74:650c Comcast requires that all mail servers must have a PTR record with a valid Reverse DNS entry. Currently your mail server does not fill that requirement. For more information, refer to: http://postmaster.comcast.net/smtp-error-codes.php#554
... while talking to mx1.comcast.net.:
<<< 554 resimta-po-25v.sys.comcast.net comcast 2601:283:4201:6300:5054:ff:fe74:650c Comcast requires that all mail servers must have a PTR record with a valid Reverse DNS entry. Currently your mail server does not fill that requirement. For more information, refer to: http://postmaster.comcast.net/smtp-error-codes.php#554
554 5.0.0 Service unavailable