Vodacom misleading service

Vodacom has upgraded me on the 22nd January and promised a lower subscription and a free handset. I received my bill where they are charging me for a handset. How did they upgrade me 9 months before I was due. I was mislead. I do expect Vodacom to respond with their automated messaging just to tick their box that they have responded. I have now spoken to more than 15 people at Vodacom, no one knows how to help.