Returned equipment was charged

Hi, I returned my equipment but I was charged on them.

Indeed there are some complications; I moved the service to a new location and asked to reuse the equipment, but a new equipment was delivered by mistake. So I requested to register the old equipment to the new account and returned the new equipment. Everything is done and the old equipment is working in the new account location. However I was charged on the unreturned equipment on the old account. Please refund me of it.