New contract Issued instead of upgrade on existing contract?!

I requested an upgrade on an existing contract via the vodacom website. I received my new phone and all was well. That was until I had to pay bill. To my shock I realized that my account shows that I have two active lines that I am paying for? Send a facebook messenger and was advised that a new contract was taken out on my name instead of an upgrade? Now the agent of facebook tells me I must provide my address for them to pickup the phone and the new contract needs to be cancelled after I have been using the new phone for almost two months? Please have someone contact me urgently in order for this query.