I filed an extension for my 2020 tax return but also sent payment through TurboTax. The IRS is now saying I owe them a few hundred dollars extra. What do I do?

The IRS is saying I owe extra money on top of the amount that I sent in, which for whatever reason, they did not receive.  I sent the money electronically through TurboTax directly from my bank account.  Is there a way to prove that I did that?