How to return internet gateway

If  that happen to you don't allow T-Mobile treat you like that, if you took the gateway in the store, just return it in the store, if they don't accept leave the device in the store and tape with your phone everting, ask them for the receipt record all conversation so them you can use it to sued T-Mobile at court, You are paying the bills and you don't receive the services you suppose to receive, T-M-Mobile think that just because they are a multimillion dollar company can do anything they want against us. don’t allow, and return your gateway in their store or just call the police.