T mobile bill against ex

Location: Pennsylvania.

Hi, to make a long story short I (20f) opened a t mobile internet account for my boyfriend (now ex) and the account was in my name, however the location and all other info was my ex’s. I did not permanently reside with him, I just stayed over very often and ended up financially supporting him😐When we broke up, I shut down the account and contacted t mobile about what I should do regarding the router. They contacted him multiple times via phone and sent letters with shipping instructions for the router, as well as paying off final bills (which he did not do). I spoke with them multiple times and paid off any remaining amount. It’s now months later and I’m getting a 250 charge for no router return. I am zero contact with him and am in no interest of talking to him directly for my own safety. I contacted both our towns non emergency lines and they essentially told me there’s nothing they can do. T mobile said my only option now is the legal route. I don’t exactly have the means for a legal case, but I literally can’t get the router and he won’t return it for some reason lmfao. Any advice?