Pathetic customer service

I took my cellphone for repairs early March to an 8ta store. Till today the phone is still with them. They are debiting my bank account monthly and on different days now even though when I got sick of being told \we will escalate"I cancelled the contract more than 3 times. Every department says its not their issue even customer service. Twitting about it didn't help as well. I am frustrated as they are now holding me hostage on their network. I keep being told we will get back to you. I am sick and tired!"""