I know this is probably not a usual question you see on here but anyways. I have over the past year purchased three different office chairs. They have all seemed fine for the first few months, however after the 2-3 month mark my back starts to hurt. There's no specific part, sometimes it's the lower back sometimes the upper back but it keeps me from doing my work properly. I sit at my desk for 8-9 hours a day( I'm a student and software developer).
I'm not sure what to do. Doing back exercises doesn't seem to work either. I don't know whether it's because I'm 197cm tall (~ 6'7'') and most office chairs aren't suited for my height? If so, can you recommend any brand or even a specific chair? It's really a problem for me, it increases my stress levels a lot on top of the pain I have every day in my back.
Any help/suggestions appreciated