Vodacom - overcharge

I have been a customer with Vodacom for around 15 years . 13 months ago i upgraded my contract to the Samsung S7. Last week the phone started to overheat- needless to say, i booked it into the vodacom shop. Today i received a message to say repairs will cost R1100. after phoning Polokwane Branch and speaking to Manager Surprise - i was told "Sorry mam, but that is the cost of replacing the battery!" Hear me out... I already pay over R700 pm for my 24 month contract but still have to pay now R1100 to replace the battery...because the lifespan of the battery is not 2 years long and the manufacturer only gives a warranty up to 1 year. Also after they replace the battery, i am only offered a 3 month warranty on the battery.!!! The phone is just over 1 year old... but i cannot stop my contract with Vodacom because i signed a 2 year contract - even though they KNEW the battery life will not last for 2 years. Also, oh, and this is really funny... to replace the battery, vodacom needs to take off some special tape and have to replace that too!!! So you also pay for that, AND you pay for the labour to have the battery replaced!! Even though you are already paying for 2 years on your contract...why do they care. If there is no service, they dont' care, if calls are dropped, they don't care. ALL VODACOM CARES ABOUT IS - HOW MUCH MONEY CAN WE MAKE OUT OF YOU WITH THE LEAST AMOUNT OF SERVICE WE PROVIDE TO YOU. This is really absolutely ridiculous!!!!!