Wrong Charges - Getting Bills from both ADT and Telus

Hi,

I was ADT customer and moved to Telus home security. Telus never informed ADT that I am now moved to Telus. ADT is still sending me bills. Now they gave my name to collections department and they are sending me emails and calls. When i call ADT, they ask me to talk to Telus and when i call Telus they ask me to call ADT. Why a customer has to run here and there. If they didn't merge properly, its their issue. its a mental harassments. Any one else too on same boat as me?