IRS double reported my money, won’t fix

Help! The IRS sent me mail saying I owe them exactly the amount I paid last year. I looked and they have my income reported twice. I talked to me employer and they did not do this, no other employees with this issue. I called the IRS a couple weeks ago and they said they saw the error and it was all fine. They said the next letter I got would say it was resolved. But, I got another one this week saying I still owe the $43k, and I had until this week to pay it. I do not owe this money and cannot find any errors in my stuff. I talked to them again this week and now they’re saying I need to call social security? I can’t get in to social security on the phone, just keep getting stuck on hold until the day is over. What the heck do I do about this? I feel like this is some sort of prank or scam, but it is not. Someone messed up on their end and I can’t find out how to fix it and this is not good.