MTN violating consumer rights with contempt.

On the 30 October2017 I purchased a Samsung Galaxy s8 from Excelltronics (pty) ltd shop 53 The Workshop in Durban for CASH (contact Said and Nadeer) . This was for my Wife for her birthday.My wife registered the phone with Samsung and personalized it. On the 10 June 2018 the phone stopped working. Because she is with Vodacom she reported it to them.Vodacom informed her that MTN had blacklisted the phone??? We submitted the necessary forms ie: Affidavit, copy of I.D. and copy of receipt to both Vodacom and MTN. Joash Seepersad of MTN said it would take 24 to 48 hours for them to unblacklist the phone. On the 18 June 2018 I went to the MTN shop in Shelly Beach and they told me it takes 7 to 10 days for a response??? On the 22 June 2018 I went to the MTN shop again and this time I was informed by the lady their, that only Vodacom can unblacklist the phone. Vodacom informed me that only MTN can unblacklist the phone . Its the old blaming game!!!! If MTN have a problem with Excelltronics then they should take the matter with them as they are basically 2 shops away at the Workshop. Why did it take MTN 7 months to blacklist the phone and for what reason????. Once again it is the Consumer who has to suffer.I paid for this phone in cash and cost me thousands of rand of my hard earned money. So now my wife sits with a phone that is absolutely useless to her and I am a good couple of thousand rand out of pocket!!!! I find this very despicable, mean, and downright ugly to say the least. I will also take this up with the consumer council for I feel my rights as a consumer has been violated.