What is the best telephone number to reach the IRS regarding my specific problem. Somewhere I read that if my refund check was a IRS mistake I have to return the check within 21 days or face a penalty and interest. I have no way to determine if it a IRS mistake or mine without a letter. My 21 days are about to expire. I called the IRS several times and the answering machine said they were not answering the phone because they did not have enough staff.
