Contract

I just want to reply to my previous review about still waiting for my phone. Vincent phone me on Friday 15th Sept 2017 and promise me that he will phone me back but he did not phone me back. This morning I receive and sms from MTN - "you are eligible for an early upgrade as your 36 month contract with MTN will be up for renewal on 5/11/2017, visit your nearest MTN store now!". What the hell is going on here. My present contract is for 24 months and not 36 months. And as you know I have already upgrade on the 5th of July 2017. So I am now very confused must I upgrade again or what.