After you file

I filed my 2019 return very late. It was a joint return. My wife had died in 2020. IRS sent a memo saying that one of the names on the 1040 was a deceased person and asked for clarification and stated I would receive my refund 6 to 8 weeks after they received clarification. They-did not ask for death certificate. I complied and have gone way past the 6 - 8 week's window with no refund check. What might I do to collect?