My verizon bill has gone from just under 300 to now over 435 a month. One month the bill was 660 another month over 1k and another month over 500. I never received the promise credit of 444 for my son’s phone. Mine was returned and although it showed shipped to warehouse I was charged the remainder of the phone balance. I’ve tried to resolve this numerous times with customer service and just kept getting the run around. You would think as a loyal customer for 15 years they would want to take care of you. Apparently not..
An accurate bill is always important to have, although the changes you mention sound like they're related to a trade-in. Have you used the tracking number for each of your trades since sending them in? They would be entered here: https://www.verizon.com/sales/digital/tradeinstatus.html , and you'd be able to see how a trade was distributed. You also mention being charged the remainder of a device payment when trading in a phone - that would be an iPhone, correct?