Why do I get lied to by 3 agents when I'm just trying to get additional service.

On the phone now for 2 hours! 3 agents flat out lie to me, nothing unusual for Xfinity customer service unfortunately. I want to get additional Internet service at another address but after repeatedly going over service info and Internet package they say we can't schedule a ln install, let's get another person on to conference in and get this set up. I say, you're not leaving, correct. They say, no, I'll be right here and will fix this. Then the next person answers and knows absolutely nothing about me or the account that was just set up and we start again. This is why you lose customers every year, this is why you have the worst customer service ever for well over 10 years, it's unbelievable! 

Edit, make that 4 agents that lie and pass me on to another agent who knows nothing about it. On the 5th now... Pathetic!