Phone Repair Issues

On the 01/03/2015 I took Black Sony Xperia Z1 with IMEI no. *** to Vodacom Repairs in Menlyn for repairs & it was booked with Job No. ***2 & the repair would be free of charge as it was still under warranty & they said it would take up to 14 days. Later I received an sms that the phone was ready for collection but to my supprise when I got there, they gave me a white Sony Xperia Z1 with heavy scratches & dropmarks off which I refused to take it cause mine was black with no dropmarks. This phone had a different IMEI no. ***, I showed it to the lady & she said she'll book it again. She booked it again with Job No. ***8 on the 18/03/2015. On the 25/04/2015 I went to Vodacom Repairs to collect & they still hand me that white phone with IMEI no. *** & this time they've charged me R4000 for their mess & for something that was not done. I told them I won't pay it & I still don't want it & they booked it yet again with job no. ***6. I can't take it anymore cause I spend money going to Vodacom Repairs & still I dont get my problem solved. It's been 2 full months & 4 days since my phone went to Vodacom Repairs & I'm not impressed at all.