Do a Google search of "Verizon hot spot phantom usage" and you will find out this is a KNOWN problem with the Verizon system......You did nothing and Verizon is well aware of their problem, but will not tell you that. Had a good friend just go through this same scenario, but his usage jumped from <9 gig to 50+ gig in a matter of several days. He fought with Verizon for several weeks, but in the end, he won and they cleared his bill and sent him a new hotspot. Verizon has a customer satisfaction team, located in Tampa and that is who he finally worked with.