Vodacom contract??? Think twice

I have a contract with Vodacom for 23 months which I honoured payments every month. I'm due for an upgrade and they tell me my scoring with them is low. I want to upgrade but they say I can't upgrade on a lower package but higher one. Is that making any sense??? I'm my score is low they want me to pay a higher premium or an upfront fee of R1000 Gosh Vodacom is ripping people off. I think it's time after many many years of loyalty to take the business to MTN SA's best network as they may be.