SAMSUNG phone will cost you more!! Battery life does not last!!

13 months ago i upgraded my contract to the Samsung S7. I have always bought Samsang as i believe it is the best. 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. Now i ask you Samsung... if you know your batteries does not last - why do you put them in the phone???? or if you believe in your product - why don't you offer a 2 year warranty on the battery as well?? You know that cellphone companies only gives out contracts for 2 years. You offer a wonderful service regarding a free screen replacement, but what is the use if i in any case need to replace the battery??? in the past (and this only happened with my other Samsung S phone AFTER 24 months) when the battery gave me problems, i could replaced it myself!! Now i need to send it in and pay for labour cost and tape that needs to be replaces as a result of them replacing the battery! 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. What is the use of buying an expensive Samsung phone - just to know you are going to incur cost in the very near future??? Rather buy 2 other phones - at least together they will last for 2 years and it will be a lot less expensive! This is really absolutely ridiculous!!!!!