AG MOBILE GOT TAB7 SECOND TAB IN 2 MONTHS

I bought a AG MOBILE GO TAB7 at Edgars Active Savannah Mall on the 10 September 2015. It started with problems. date and time tuning out and going extremely hot and then going dead. and for a long period of time struggle to get it on again.It lasted for a few minutes and go off again.I try to charge it and then it do not want to charge passed 15%. and so it goes. And then for some reason it went to the Android screen and it stuck there. Then it went dead for good. I took it back to Edgars where I bought it and AG mobile replaced it after 3 weeks of fighting and the phone just lying in Edgars Savannah Mall drawer. Nothing done yet. Only after I start making a noice things start happening. Anyway. 3 Weeks later the second AG MOBILE GO TAB 7 have the same problem!! I sit with a device thats dead. Went back to Edgars today and now they want to book it in for repairs again. I am not happy about this. I want a refund. Bought a phone and twice it got the same problem. I called AG MOBILE on their *** and the phone is just ringing. Before when I did get through they are not very friendly or helpful at all. Just tell you to go back to where you bought it. I am fedup.