Iphone 6s using the standard email software.
I have an individual that is receiving email from a coworker, but when it arrives on that persons iPhone the common name associated with the email address is incorrect. So they delete the email and say they have never received it
Put another way
Person "A" sends an email to Jim Smith at firstname.lastname@example.org, when it arrives on Jim Smith iPhone the name in the to: address is Tom Jones.
I've looked in the contacts on the persons phone for Jim Smith and Tom Jones to make sure there wasn't a mix up there, no problems there, anyone else that is cc'd in the email has not problem, the email is addressed correctly
Where else can I look