MOST HORRIBLE SERVICE AND DAY LIGHT ******* FROM VODACOM

My wife and i bought mini tablet for our son at vodacom Makro in wonderboom for R799 as it was on promotion after 2 months of purchase we noticed when ever the tablet is fully charged 100% it doesn't last 2 mins it finish to 0%. Took the tablet back to makro wonderboom it was booked in for repair with job number - ***1 few weeks later i was informed the device cant be repaired it will be replace and was quoted R950 for a demo tablet as replacement which I rejected the quote and asked the tablet to be returned back to me as I don't understand why the tablet can't be replaced under warranty. I was informed the tablet is ready for collection which I went to collect, only to discover the tablet doesn't charge anymore at all it only flicks on the screen when been charged and the tablet doesn't switch on anymore which never happens before I took the tablet in for repair. This is totally unacceptable and I need urgent feedback on this horrible service and day light ******* from vodacom and makro the tablet is not even upto 3 months from date of purchase.