>>20203506This happened to me before. Somebody bought a couple phones in my name and ran up a bill of a few thousands dollars. It seriously fucked up my credit score and I had to jump through all kinds of legal hoops to prove my innocence. The entire time I wasn't even convinced the "collection agency" I had to deal with was even a legitimate company and was worried I was somehow being further scammed by them. Luckily that wasn't the case, but the whole ordeal still took months to finally get everything straightened out and settled. This was over a decade ago so hopefully for your sake they've streamlined the process.
