I had the EXACT same situation as verbaltek. Received my replacement iPhone on May 1 and mailed the defective device back to Ft. Worth in their box with their shipping label on May2. Followed all instructions.

Received text several weeks later that I would be charged $599 for equipment that was not returned. Made 4 calls and have been treated rather poorly by customer service. I have been a customer for more than a decade. Everyone in my family is a customer (mother, father, sister, aunts & uncles, cousins). NEVER had a late payment.

Each customer service person has told me a different story. In one case, the device was not received. In another case, they located the device and I would be credited. When I followed up 5 days later, most recently, another agent and supervisor told me they found an empty box. This is OUTRAGEOUS. I have been with verizon for so many years because of their outstanding customer service. I am shocked by the way that I am being treated. Supervisors leave me messages with phone numbers where they cannot be reached and I am waiting now for 8 days for someone who was supposed to call me on June 12. I am switching to ATT or SPRINT.