Amazon review: Charging my amazon credit card instead of my gift card

I have been loading my amazon gift card to make purchases and have amazon credit card but don't use it and my balance was 0 in the month of July this year (last month). I have been making purchases in this month of August and when purchasing it always shows me I have enough balance to cover my order but then today, I find that the higher ticket charges are being charged to my amazon credit card instead of my gift card.

So, my painful journey of being ridiculed, disrespected and totally ignored by amazon. I have been calling, chatting but cannot get to any manager - they hide and don't want to face customers because they know Amazon screws customers at every step and they are getting their fat paychecks so who cares. Suddenly from 0 balance to $1775 balance went up and shocked me. I have been since trying to get this balance back to 0 and talking to everyone but have been tossed like a salad in a spinner without any consideration or decency.

Even called the corporate office where they basically said no one will talk to me only customer service will handle your case and disconnected the call. Still to date I have no resolution and still struggling to get my credit card sorted. I'm at my wits and in tears now with high blood pressure, migraine and angry.