someone used a fake ID to buy sim cards

This just happened to me last week! I've a phone notifications that I've purchased two sims cards and I quickly called T mobile and was told that someone used a fake driver's license to purchase two SIM cards under my name at a t mobile store!!! How could this happened??? My questions to T-Mobile is why can't you tell me which store the thieves went to get the SIM card from? I was told by T-Mobile CSR that this won't be reported but if I want to I'm welcome to?! Why is this not reported to the police by T-Mobile? Does T mobile just feel identity thief is not their concern if their customers account have been compromised? 
I have never had any identity theft before and I didn't do any unusual purchase that required ID or gone to any site except I went to t- mobile store once to make an enquiry about my phone line and months later, I had this identity theft issue! Coincidentally the store I went into, was no longer there in the same location! That's the only place I had to show my proof of ID. It's definitely suspicious! Although t -mobile rep said they won't charge me that two SIM cards and had terminated the lines & reported it as fraud…  it is still a major concern that "someone" could walked in to their store to present a fake ID OF ME! That's very concerning! It is not enough just to say T-Mobile cares about their customers but yet don't report this or share which store the fraud being committed.  I'm sure the store has had transactions, cctv recordings to trace the culprit. Yet, no information can be shared with me where was to store located & what type of ID card was shown? 
Has anyone else experienced this? What did you do?