I would be lodging complaints with the FCC/FTC and local BBBs. Not only have the overcharged you, but they watsed your time, called you a liar, and put the onus on you to avert cut-off instead of assuring of it themselves. My view always is that the company's internal workings are not of my concern - I am a customer, they have done me wrong, they need to fix it - it's not up to me to navigate their corporate structure to resolve the matter.

If not, that's what LNP is for