Last April I had moved and my AT&T internet wasn't working at my new address so I closed the account, paid the last bill, and sent the modem back. I checked my credit this week and my score has gone down 90 points because of a report from Southwest Credit Systems. I called and they said it's from AT&T. I asked what the account number was and she gave me a 9 digit number. I went on AT&T's website and saw that 1) my account number was 10 digits and different from the one she gave me and 2) it showed that I had paid my last bill 04/05/15 and had a zero balance. The chat with a CSR box popped up and I told the guy, Eric, what was going on. He seemed genuinely concerned and told me when the last bill and paid, that they had no right to report anything, and that he would escalate that matter to his supervisor, who would give me a call back the next day. It's been three days and no call. My concern is that Southwest had the last 4 digits of my social and that they knew the account had been closed in April- which leads me to believe that for some reason AT&T did send them my information. I just don't see why, if I owed AT&T money, they wouldn't call me or send me another bill before sending it to collections. I haven't called AT&T or Southwest Credit yet because I don't know how to go about this. All I know is that I need to get what Eric said in writing. I'm only 22 and had above average credit before this, and now I need to get a loan to go back to school so I need to get this fixed as soon as possible.