iMessage shows the wrong name for a phone number
Try closing iMessage (Settings > Messaging > iMessage).
Turn off your phone and wait 5-10 minutes.
Tap Settings > Phone > My number and verify that your phone number is correct.
Finally, reopen iMessage (Settings > Messages), then go to Settings > Messaging > Send &amp; Receive and see if the correct number is displayed under "Start a new session from".
Hope this helps you.