How do I get action to resolve a billing issue?

Purchased two iPhone 12 Pro Max phones as part of a BOGO promotion.  First bill came and promotional rate was not reflected.  I have spoken to several live agents and live chat agents at this point in an effort to resolve all who promise to investigate the issue and call me back.  So far every commitment to respond has been missed by Verizon despite promises otherwise.  Extremely disappointed as a long time customer.  Issue remains open going on 4 days now with no feedback on when I might expect a response.  I don’t have time for another hour long call with a new agent just to bring them up to speed on the issue and more false promises for closure.  Does anyone have suggestions on how I can escalate to get some action?

Re: How do I get action to resolve a billing issue?
Specialist - Level 3

Just a heads up. If you called back within 7 days, you ruined that agents stat which gives them zero reason to call you back.