Willy Nilly Blacklisting

I bought an Galaxy Note 4 from [URL Removed] and used an MTN sim card on the phone in Jan. On 29 April, the phone stopped picking up signal and went into emergency calls only mode. I went to MTN and was told its a sim problem and should buy a new sim card and RICA it again. Of course I knew this was utter nonsense so I decided to take the phone to Samsung who returned the device with a note informing me the device was blacklisted. I took this up with MTN who informed me they were instructed by 8ta to blacklist the device due to bad debt. What bad debt when I have nothing to do with 8ta and bought my device for cash from Kalahari? My attempts to get 8ta to fix this mess have been met with \Sorry we are offline"I have phoned them more than 4 times and I keep getting this useless response.<br> <br> I am literally pulling my hair out and do not know what to do get 8ta to unblacklist my device. I am equally irritated with MTN who just blindly carried out 8ta dirty work without warning."""