I ACTUALLY got through to a human being. You can't use the 1040 number, all you'll get is "due to excessively high call volume, your call cannot be completed ...." Use 1-800-829-0115. Then, press 1 for English (assuming you understand English), then press 2 (unless you received by mail one of the letters they list, in which case you press 1) and then it will ask for your social. After entering your social, confirm it is correct by pressing 1, then you'll hear seven topics. Press 1 again, to "set up a payment plan." Even if that's not why you're calling, press 1 anyway. There was a 15-30 minute wait when I called. It took 25 minutes, then a human answered, and resolved my issue. So again, call 1-800-829-0115, press 1, 2, enter social, press 1, 1. Good luck!
