Awful Customer Service

Second communication about a billing error. I verified first responders discount supposed to be applied already and I even had proof of the chat with previous rep (Rose) who also indicated there would be a credit applied (in the chat) however the next rep when I called to correct it again (Tristan) and Supervisor (Michaelangelo) would not honor the proof of their error and just completely evaded the request to credit and change over and over again, it was messy and tacky, I'm so done.