Yes I did file an amended return, explaining in an attached document / letter why the W2 was incorrect.
It took several years before the IRS refunded the overpayment with interest. You have to do the filing within three years of the original return due date. Keep all documents and proof of mailing. They disputed the timing by saying it was too late to file, taking the date of processing for their argument. I protested with the certified mail receipt showing the mailing date was within the three year limit.
Good luck
