Complaint - Unwanted Upgrade

Complaint:Upgrade of contract without consent given, Vodacom upgrade call centre is harassing me everyday for contracts to be upgraded even though I am still paying for devices and I know exactly when to upgrade, I informed the consultant on the day that we spoke that I am not willing to upgrade my contract and that stage as I am still deciding, this morning at Came in the morning I received a message that my contract was successfully upgraded, now I lost my data that I had because very little pro-rata was given on the upgrade, the after sales department assisted. I just want to know is this business is being done, force selling clients and doing unconsented upgrades on clients accounts. I expect feedback from Vodacom