Poor service

I took out a contract at Vodacom, a Sony m4aqua about 3 months ago. The phone has been back to vodashop tygervalley for 3 times in a row for repairs. Every time I receive the phone from the repair centre the phone is still faulty and the cover of the phone is still loose when received from the repair centre. They dont even have the decency to send the phone back in the condition that they received the phone. This is a new phone, is it suppose to do this? I'm paying a fortune for a phone that is no use to me, because is more in the repair centre than with me. This is not the first time I've experienced this problem with Vodacom and it's phones