You can look at your previous bills by going to My Verizon>My Account>View bill and then using the drop down menu. That way you can find the trade in credit, do you remember what the credit amount was meant to be? What phone did you trade in?
I looked at it and I cant tell what is what. But it does show a balance of what is due in order to pay off my phone through the edge program. I factors in the credit I think.
It's unlikely it factors in the credit. The Edge contract and the trade in are two different things and to keep things straight they would have just given you a trade in credit in order to keep your Edge contract at 2 years like it's meant to be.
What phone did you trade in? You don't remember the trade in value? My thought was it some how had a trade in value higher than $300, in which case the Verizon Rep was thinking "trade it in for $400 and then when you get the $300 bill for not turning in a phone, you're still up $100"