Reversal of upgrade of cell contract

Upgrade on Vodacom Contract - ***, got CAT B150 on 7/10/2015, took it back in original packaging on 12/10/2015. Phone very hot and battery after full charge did not even last a day, only 4 calls made. Told Monique that we want another phone, not a CAT again, she called her manager Riaan, which told us he will send it back to HO, and let us know. On 19/10/2015 we went back, no feedback from them, we told them to reverse the upgrade. We went back on 28/10/2015, we after Monique explained that she hasn't received any feedback from HO, her Manager will phone us. We called him ourselves, he will get back to us, on 30/10/2015, they got credit from HO for the phone, but we don't want to proceed with the upgrade, as we are not happy with their service, we want it reversed, will do the upgrade with Vodacom directly. Spoke to Patricia @ Vodacom Regional office, she has escalated the case, but it seems that everybody is stalling, as we are now out of the 14 days to do the reversal, and now they can force us to keep this upgrade