I have a 4k debt from a credit card company, who sold it to a a debt collecter. My question is, I agreed to a certain amount each month and they have raised that amount by 50% without me consenting. Is this legal? They also chastised my girlfriend and talked in detail about my debt with her. I'm just wondering is this all legal? Also....are these companies allowed to add interest on your debt since the bank has sold it to them?