When you amended yours to change/correct it?
It can take many "months" (or never) for the change to get fully corrected in the IRS computer e-file system. Some experienced folks even indicate it never gets changed in that e-file system .
As such, he can still file, but he must print his tax returns out and mail them in. When he does, he should make sure he uses a tracking system (Certified) at the Post office mail counter. Sign, date, attach any W-2 forms or other tax forms showing tax withholding on them. State forms DO Not get mailed in the same envelope...they go to whatever state tax office is appropriate.
____________*Answers are correct to the best of my knowledge when posted, but should not be considered to be legal or official tax advice.*