if you got a check don't cash it because if IRS made a mistake you can send it back. you do need to call to find out what happened. direct deposit. - when speaking to IRS ask what to do.
if line 21 is blank you made a mistake in completing your return. no need to call.
you ASAP make the payment that you intended to be applied. you can go to IRS website and use direct pay. be sure to print receipt.
