28 Days Later but no help

Can I please get help. All I want is to download BIS on my phone, the error that is showing is that I am need to cancel my BB10 in order to do that, I have a Blackberry 9720, how does this phone have BB10 ? I have tried everything , calling everyday for this problem but no help. Even visited a Vodacom shop/ customer care but I could not get ant help. <br> <br> I HAVE NEVER BEEN THIS FUSTRATED IN MY LIFE .I mean its been 3 weeks now but no help <br> <br> For trying out load, I have been a customer for more then 10 years. Thinking of going to MTN OR 8TA