Sold me a blacklisted phone

I purchased a Samsung Galaxy S5 @R6999 from this store and a few weeks later I was unable to make calls nor send sms's. I took the phone to a Samsung repair centre and they advised last week that the phone was blacklisted due to bad debt. <br> <br> I was confused as the phone was purchased and not taken via contract. IMEI is ***. I have tried contacting the branch but the agent Ariana Govender doesn't respond to my emails lately....I'm left to deal with the inconvenience of a loss of money....maybe a deal too good to be true