This number sends a text asking if an item you put up for sale is still available. Then the person says they would like to buy it and they will send a certified check and arrange for shipping of the item. The certified checks are bogus. This is a scam. Even if your bank accepted and deposited the check it eventually comes back as a bad check. By then your item will be gone. They even offered to add a little money to pay for your troubles. Be careful and don't fall for this scam.