Terrible experience with ATT

Terrible experience with AT&T.
1. Suspicious: They sold stolen phone to customers for upgrade alternatives.
2. Suspicious: They helped thief to unlocked iPhone!
3. Violation: They hided the insurance charges information and never informed me that I have insurance on the phone neither when I was purchasing the phone nor when I was reporting/finding replacement for the stolen phone.
4. Violation: They reactivate my stolen phone for the thief after I blacklisted it, without my authorization.
5. TERRIBLE COSTUMER SERVICE. Reps are unknowledgable, unfriendly and unprofessional.

I had my newly upgraded iPhone 6 stolen on February 7th, 2015 and I suspended my device immediately. The phone was surely locked with password while it got stolen. I went to AT&T store and Apple store and took all the steps that I could do in the situation, fully followed the representatives' instructions.
1.I wasn't able to locate the phone because the thief shut off the phone.
2.I requested to erase my phone but the request got pending for two months because the phone wasn't in wi-fi environment.
3. I reported it stolen and ATT people said it should be on blacklist. Anyone wouldn't be able to use it.

However, on Feb 14th, my iMessage received unexpected texts. I could see the texts between the thief and another unknown person because he was using my iCould account, which means he passed through the password and got access to my iPhone. In the texts, the thief was bragging that he stole an iPhone 6 and he was at an AT&T store to do something. Notice that, he started to be able to use my iPhone to send texts at the moment he arrived ATT store! What can I assume then? Who else can help him at ATT store to get access to an locked phone?

I went to an AT&T store immediately to ask why he was able to get helps at AT&T store, got access to my iPhone meanwhile and why can he keep using my phone after I report the stolen. The representatives were not helpful at all and denied the possibility for them to help a costumer to unlock a phone. I'm 100% sure that I don't know the thief so he didn't know the password. My lock screen even appeared a clear photo of me, which I think anyone would notice the difference.

I called costumer service to confirm if it's still on the blacklist. The IMEI shows that it was reported stolen in Feb. However, on the record, it has also been reactivated on April 23th and on that day, I got message from my iCould account saying that my request of erasing the iPhone 6 finally got through after two months pending. So the thief has already reactivated my stolen phone while I am still paying the bill. I am extremely terrified by the fact that the thief could be able to reactivate the device without my authorization. I was told that only the person who has my account information/personal information can reactivate the device. That can be considered an identity fraud. OR there's another way to explain it:

One of the representatives I spoke to told me that: from the IMEI number recorded, she saw the phone was reported a stolen phone back in 2014, which means the phone was on blacklist back in 2014 before I purchased it. However, I purchased the phone from an AT&T store as an upgrade alternative. She told me that may explain why I couldn't get the phone onto blacklist and why other people could also reactivate the phone. It's because I am NOT the initial owner of the phone. If that's true, I have to ask, why employee at AT&T sold a stolen phone to me? How many other people like me got stolen phones from AT&T?

That's not even the whole story. I realized yesterday (June 1st) that the device has insurance since last October, which I have no idea the entirely time. I went to AT&T store to report the theft and tried to find replacement many times but nobody had ever told me that I have insurance for that device. Certainly nobody told me in the first place when I purchased the phone with the insurance. It appears on the bill that I got the insurance along with the upgrade. I am not the primary account holder and wasn't paying attention into every bill that I paid. I don't work for AT&T and I didn't know being a customer at AT&T could've been SO DIFFICULT AND FRUSTRATING. But I still have the right to know the insurance status in the first place, right? I called again to costumer service and got terrible attitude and an answer like this: "The insurance charges appeared on monthly bills so it's not our fault that you don't read the bill, and IT'S NOT OUR FAULT THAT YOUR PHONE GOT STOLEN! If you have complaint of the agent who sold you phone in the store, provide his name and his manager's name, otherwise we cannot help. Oh, you don't have any names? GOOD. Even you have names, they probably are not working at AT&T anymore. There's nothing more we can do to help. I feel sorry." Those are the words she used in the phone interview and it's recorded.

I called the insurance company yesterday, of course they said it's too late to file a claim because the phone was stolen 5 months ago. They only accept claim within 60 days. They didn't care what do I think about AT&T and told me that's AT&T's responsibility.

I think AT&T definitely has responsibility for the costumer service behavior as well as the guy who sold me the suspicious phone and hided the insurance charges. THOSE BEHAVIORS ARE FRAUD!

With hours and hours of calls, I NEVER got any straight answer from AT&T's response for months. What I got is only confusion and anger.
After all this questioning and frustration, it's difficult and ridiculous for me to keep paying the bill for the stolen device and the forced insurance. I will definitely switch to other carrier and wouldn't recommend anyone to use AT&T and the Asurion insurance.