I had a new twist this year on rejections.  Long time client got married a couple of years ago.  His stepdaughter graduated from college in 2023 and was out on her own.  I filed her return and it got rejected because she was claimed as a dependent on someone else's return.  Client's wife calls up the ex and asked why he claimed their daughter.  He gets pissed and says that he hasn't claimed her in years.  Well, he thinks he hadn't claimed her in years, but the tax preparer wasn't following the same playbook and had been claiming her for years.  Another classic case of someone closely reviewing their return each year 😬