Bad service from Vodacom

Hi my name is Florah took contract with Vodacom 2years ago, my contract ended last year.This year somebody from Vodacom decided to use my details to take iphone to deliver it toBrakpan and therefore Vodacom decided to deduct an amount of R1197.00 from my account.I went to Vodacom shop at Wonderpark ,but i didnt get any help ,they gave me no to call , i ended up reversing my money from my bank.And this month they deducted R614 from my account, they charge me with their interest ,is not my fault.Now they blocked my phone i cant make calls because they told me about owing them R 21000.00 .i cant cancell the conract because of this dept. Please help .Iwill never use their service anymore Regards Florah