What should you do after a CS agent hangs up on you?

I was trying to make a payment today and I was hung up on by an agent named Rozenna after expressing interest in speaking with a supervisor following that call. I called back immediately and went through the prompts again and was again connected with Rozenna, who denied ever speaking with me before and said her shift just started, although she had information regarding my account and situation that she would have only had from the previous call. When I finally did get a callback from a supervisor, I was told that the sup calling me back was not in fact Rozenna's supervisor but could look into the matter, although they have no record of the first call whatsoever even though I called from my primary Verizon cell phone and can prove the call was made. When I asked to speak to Rozenna's supervisor or have a callback from her direct supervisor as I was expecting, I was told there was no way to do that which seems odd to me.

Does anybody have any advice to make sure something is done and customers aren't treated rudely and then disconnected for no reason? Calling the 800 number and going through all of the prompts and waiting again isn't ideal. 

Re: What should you do after a CS agent hangs up on you?
Customer Service Rep

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