Samsung S5 nightmare

<p>I got a Samsung S5 early 2015 via a 24 month contract with MTN. Initially i loved the phone, battery life was great - lasted 2-3 days from 100%. Then a couple of months ago i was FORCED (take note i tried to avoid this!) to upgrade the software from Kitkat to Lollipop. Immediately my problems started. The battery drains super fast and the phone overheats. I now HATE this phone. It needs to be charged at least 5 times a day, the battery would drain from 50% to dead in 20 minutes. I've taken it to MTN's technical repair centre in Durban and received it back yesterday. They confirmed the battery is fine and of course installed Lollipop again after doing the factory reset. The problem remains unchanged. I know Samsung is aware they made a huge mistake when Lollipop was introduced to devices that cannot cope with the software, there are thousands of similar complaints all over the internet. Please tell me Samsung, what am i supposed to do??? I am stuck with a useless phone now! You have just lost a long standing customer. We are a family of 4 used to buy Samsung products...</p>