IT Shop Emails not goin thru

Hello All,

Has anyone seen this error before when IT shop emails are being sent?

ErrorMessages = (2019-08-16 13:59:50.480) [2425008] The definition does not match any valid mail user definition string.
   at StdioProcessor.StdioProcessor._Execute(Job job)
   at VI.JobService.JobComponents.MailComponent.Activate(String task)
   at VI.JobService.JobComponents.MailComponent._SendRichMail()
   at System.Linq.Enumerable.ToArray[TSource](IEnumerable`1 source)
   at System.Linq.Buffer`1..ctor(IEnumerable`1 source)
   at VI.JobService.JobComponents.MailComponent.<_GetMailUsers>d__13.MoveNext()
   at VI.Mail.MailUser..ctor(String definition)

I have the following environment...

Version 8.0.1

I have the Process Component "NoTransportSecurity" set to None.  Our FW department says they are not blocking us....

any and all your help would be greatly appreciated.  Currently we are not getting emails to go over to business.