Installation fee wasn’t waived as promised by the sales rep. How to solve the issue?

I set up a new Verizon account with a sales rep on 3/16/21 afternoon. I had Verizon fios before, but to set up this new account, Verizon forced me to upgrade to their fiber WiFi even though I told them I did not need speed higher than 100/100. With the upgrade, a tech must come to my house so there is a $99 installation fee. The sales rep checked with his supervisor a few times and promised me that installation fee will be waived and won’t show on my first bill. Then I asked the reps name and if there’s a confirmation email or reference number I could refer to in case the installation fee shows up later on my first bill. The sale rep named Paul gave me a reference number. 

I received my first bill this week and a $99 installation fee is on my bill, so I called yesterday on 3/24 to talk to the billing department with my reference number. However, the billing department said there was no such reference number and they did not see any notes under my account showing the installation fee should be waived either. So obviously the Verizon fios sales rep was lying about everything in order to get new customers and his commission. Next time I call Verizon service I have to record every single conversation between the agent and myself. And then billing department promised they added request to waive my installation fee this time and the credit will show on my account today with an updated bill. 
Again today when I logged into my Verizon account I don’t see any credits. 
what’s the best way to speak to supervisors or complaint department? 

Re: Installation fee wasn’t waived as promised by the sales rep. How to solve the issue?

Hi llou,

Your issue has been escalated to a Verizon agent. Please check your Private Messenger Inbox for a message from a Verizon Support agent. You can find your Inbox by clicking on your username at the top right corner of this page and then clicking the envelope icon that appears at the top of the menu. Response times may vary and may be delayed at this time. Please continue to check your Inbox for a reply from a Verizon agent. Please direct all correspondence concerning your issue to the agents who will be assisting you privately.