I have come to the conclusion that elevating your "concerns" to a supervisor at these larger service providers is the way to go, nine times out of ten. Give the person who answers the phone a shot, but they only get one.
There was one instance last summer where I even went one further. I asked to speak with the supervisor's supervisor. She told me she was a supervisor. Somewhat surprised that I wasn't cursing, but I know that is grounds for an instant and rightful hang up. I was so boiled over, that I said something to the effect of, "Supervisor is probably in your title, but unless your name is Jeff Bezos, there is someone above you. Please put that person on the line." Eventually I got satisfaction.