bad repair

I gave my tablet in for repairs at vodacom in klerksdorp, they send it away to potch vodacom repairs. Middle/end February. Reason because its charge for almost 2 days before its fully charged and it freeze when you do something on the tablet. So they send it back because there was a log on screen and imei number on box and tablet is not corresponding. Second time I send it in, with the correct box, to potch came back and tablet is still not working properly. Still freezing, charge for 2 days, tablet is getting warm, puts itself on and off. Screen goes black. Round about middle may I gave it in again in klerksdorp to send it again. And I asked to send it directly to vodacom headoffice repairs. They send it to potch, and potch tested it and they send it to headoffice. After almost 2 weeks I got the tablet back, power source unit was changed. AGAIN...... tablet is charging 2 days then its fully charged, screen goes blank but background music is playing, tablet is getting warm, freeze. Im really very disappointed in this POOR service. Im paying for something that we can hardly use. How many times do I have to send it in before it will be fixed 100%.