Trade In Issue

I sent in my perfectly good working condition phone for trade in as part of the android/samsung $800 trade-in deal. I had it wrapped in extra wrap, in 2 packages, still in the protective case with screen protector. ATT is saying my screen was broken. I have called multiple times to discuss this with someone since my phone was not broken when it was sent, and all I have received is the people telling me they have escalated and cannot do anything else. I have not heard back from anyone yet; my case has been escalated 3x now. I would like to discuss this with someone! I had a friend turn her phone into a store with the same deal except her screen was shattered and she received the $800 credit, why do I only get $22.50 market value for a broken screen (that was not broken before!) but she got the full amount? I would like answers and help with this....getting frustrated and very disappointed in ATT