Lethabo

I want to Cancel Contract With blue label they gave me old iPhone 5s with expensive money and that phone battery runs fast it doesn’t last longer I put it on charger after two minutes Battery is empty.i called one of ur customer service to help and he says that is not their problem that phone is not working.he said why do u allow them to give u old phone so I Want To Cancel a Contract With Cause I won’t pay for a damage battery phone so pls help me