Won't even cancel their invoices billed on their staff's error

They double billed my account on LTE product which l don't even have and now they keep going roubd and round in terls of giving feedback and cancelling the two inaccurate invoices. Now l must suffer as a customer for their *********** staff.. If only they could replay the recordings of my phone calls, they wil' find out that all their agents kept confirming that l no lonher have an LTE product, but wbo cares to check? I'd stay away if l were anyone else. Supersonic will rip you off with double invoicing eventually.