"Simple" and "phone call" are generally not found in the same sentence when discussing IRS, but I'll take your word for it.  How does the person at the other end of the line know it's the taxpayer?  (And I hope the preparer isn't allowed to do it.)

Helped a client a couple years ago whose family member died in early September.  The scheduled payment for September 15 was rejected by the bank.  IRS charged a penalty of $40.  Wasn't worth a simple phone call to try to get it back.