Samsung S8 plus

I can't begin to explain how upset I am with vodacom and Samsung. I have been a loyal customer for many years and if this is the level of service a customer receives perhaps I need to reconsider the brands I support. I upgraded on the 17th September at vodashop Clearwater mall to a Red package and selected the Samsung S8 plus. Upon receiving the device the device battery was not lasting even half a day. I returned the device on the 19th September for an out of box failure and the store sent it in for repairs supposedly at Samsung.. No communication was received in terms of device progress and on the 26th September I then received feedback that no fault was found, a software upgrade was done and I need to collect my device. I requested this matter be escalated as the device should have been swopped out. The store advised me the best they can do is give me a further 7 days to test the phone. I collected the device the evening 6th October and returned it the 8th October as the phone was doing the same thing. Yet again poor communication in terms of device feedback. Eventually i got in contact with one of the store managers William who advised my device had been sent to the advanced repair centre. Following up yesterday yet again they advise theres no fault with the phone and it has been dispatched back to the store. I would need to rebook the device and escalate if I am still not happy. I am not prepared to accept this device and want it replaced as I cannot be doing this back and forth and im well within my CPA rights as the product provided to me is substandard and not of good quality. I have been using samsung for many years and how is it possible that my current s6 edge over 2 years old lasts longer than the s8 plus which is supposed to be a better device with a more powerful battery. I'm at my wits end to a point that I'm extremely disgusted with the service and run around I am receiving and need a desperate intervention to have this matter resolved. Why is it that we have to complain and escalate just to receive items of good quality and proper service!