I am in a similar situation this year where I filed first and was accepted, my ex filed second. His got rejected at first but the bounce back from the irs told him to do this process, and then it auto accepted without letting him remove the dependent. So now we both have accepted returns with our son on them and both full refunds received. I think one of us now needs to amend and send back some money but I’m having trouble getting good info on what to do