MTN selling fong kong phones

i purchased a Hisense cellphone from Woolworths Northgate mall branch and within a month the phone was not charging and i took it back to woolworths and they booked the phone in at mtn for repairs. i had the phone for less than 7 days after repairs and the phone just switched off and died nd would not even charge. i returned the phone to woolworths again for the 2nd time and the phone was booked in again and i only received the phone after 5 weeks and i was told that no repair has been done because of water/liquid damage. i called the woolworths complaint line and to date i have had no feedback. I am not sure if MTN is trying to rip me off or what because i paid cash for that phone and in less than 3 months it went for repairs twice and now i am sitting with a new dead phone but i am sure if it was a contract phone they would be calling me non stop for their money. I am really dissapointed in MTN and i honestly did not drop the phone into any water, i want my money back from woolworths/mtn.