Your issue Is EXACTLY what happened to me. I went to the Chapel Hills Mall Verizon store on 24 Dec 2017 to purchase a new phone. When I got there, the manager convinced me that the iPhone 8 BOGO promotion was better than just buying the phone outright. Of course, it required that it be paid off in installments, which I didn't want, but I went with it anyways. It also required the unlimited plan, which I also didnt want to switch too, but that had to be part of the deal. There was never any mention by the manager or in the paperwork of the requirement for a new additional line being added when I bought the phones. He also stated that the promotion would be credited on the 3rd billing cycle (March), and when that date came and went, I began contacting Verizon about the credit. I also recieved the same "escalation"
run around you did, and eventually Verizon just blamed the manager who sold me the phones of being incompetent and lying to me. As far as I'm concerned, its been almost 8 months without an appropriate resolution, so Verizon is clearly in breach of contract, which voids the contract. I informed verizon twice that they are in breach of contract, and after today's unpleasant conversation with them in which they now say I was never eligible for the promotion after telling me for months that the promotion credit should have been applied, I am returning the phones for what had better be a full refund and cancelling my service. Verizon is clearly in breach of the contract terms and conditions; whether or not they set out to commit fraud is debatable, but they are definitely not honoring their agreements.