Total Wireless won't activate my cell phone

I purchased a total wireless phone. I bought it from someone on Craigslist. Third party. I've been trying to activate it , but total Wireless won't activate it. They say the phone was never scanned at the register when it was purchased by the original owner. According to Total Wireless there's nothing that they can do to help me unless I have the receipt for it and then to also have it scanned at the original store it was purchased from. I don't have the receipt for it. I don't know what store was originally purchased from and I can't get in touch with the original owner. Is it possible to activate this phone through any other means such as changing the IMEI number is that a possibility? Is it possible to switch it to another carrier or will total Wireless prevent the device from being transferred? Is it total Wireless that is preventing me from being able to activate the phone or is it just legitimately not able to be done on their side of things.