Rain billing for no services

Rain was sold to me as a prepaid services. when you don't pay they cut your service. fair enough. Due to no income I cancelled or did not pay for the new month. i tried to contact them to collect their device. very hard to get hold of them. they phone me to tell me i owe them 2K. So regardless if the devices is activated or not they still bill you ? how does that work. sorry that is unacceptable . i will not pay for a service not provided. I was told if i no longer want the device i must just contact them and they will cancel it. Is this now an easy way of making money? There is no support centre, or someone to talk to . i had to use the mail when my services was first connected