I filed “married, separate” need to amend that to “married, jointly” has anyone had to do this?

My wife did not work and had zero income.  I filed married separate returns thinking that she would not have a return to file.  It dawned on me that I should if filed married jointly with her having zero income to claim a pretty decent tax break.  Well I tried to amend it electronically and it was rejected.  Is it possible to fix this?