Complaint Review: T-mobile

I bought V24/7 telephone services when travelling overseas in Japan & Vietnam from 3/30/16- 4/17/16. I understood if I did not request or authorize T-Mobile for roaming  charge $5.99/min services then T-Mobile should not charge for this service. T-Mobile illegally charged me $629.09 for the service I did not request or authorize and was not aware of this till I get back to USA (see attached file). Each time I made calls using V 24/7, V 24/7 phone operator told me that amount of money & minutes I had left so I understood that what I paid for. T-Mobile automatically charged outrageous roaming services without my authorization or request.

I contacted T-Mobile on 4/24/2016 and spoke to supervisor Dewayne, he said will give me $100 credit due to charges for services I was not aware of I told him that as a consumer I felt defeated by T-Mobile. I would like to discuss issues with his supervisor. He transferred me to manager Valerie then she told me she would not honor it.  As I understand if consumer did not request for roaming services then any phone calls would not be allowed to go through. T-mobile actually defeated customer so T-mobile can charge consumer whatever the amount they want