Rediculous Upgrade Service

How ridiculous is this, I got a sms from Vodacom saying I can upgrade in the first week of November. All went well got my new devise, all happy go lucky until I received my bill yesterday stating that I am still paying for my previous device. Phoned Vodacom immediately to only find out only then that my actual contract is only expiring in February next year. So I still have 3 months to pay, which I did not budget for. I have been a client at Vodacom for a very long time, no one explained this to me otherwise I would have waited until February to upgrade. I think it was done in a sneaky money making way which is highly unacceptable and I will be taking legal action regarding this matter. I would definitely NOT renew my contact with Vodacom next time. Very unhappy client!