BAD CUSTOMER SERVICE

Hi, I have a contract with Vodacom which I'm paying R368.00 per month however my problem is I been paying for a phone I don't have ,I started to experience problem on December 2017 and I took it back to Vodacom and they promised to fix .on January 2018 I went to do follow up regarding the phone .i advised that the phone was fixed and they gave it to me ,however the phone was not fixed and I took it back 4 times to the store . I'm not happy with their communication ,they don't update me I have to go to their store everytime I want to know about the progress with my phone. And when I try to end the contract they always have excuses and say I must give them a chance . It's been 6-7 months without my phone but debit order is going through my account. They lend me a phone which is on the standard of the phone I'm paying for and should anything happen to it I'll be held responsible for it.