Home Internet Unit

I hope someone can help me remedy a very frustrating situation. I got my text from T-mobile indicating the amount of  my next payment. To my surprise the amount was over $200 more than normal. I logged into my account and it said it was a charge for not returning a Home Internet Unit. The situation of not returning a Home Internet unit is not true. If it was true what would I do with a Home Internet unit with no service activated on it? I spoke with customer service for nearly 2 hours with out a resolution. This company has definite issues and I’m not sure where to go from here.