Royaloak Furniture — Computer Chair After Sales Service issue

I purchased a computer chair from Royaloak Kochi shop (Invoice #SI[protected] and within 11 months its backrest had issues. Backrest tilted towards the back and not returning to its original position causing backpain. I tried to call their Kochi office but unfortunately the number provided in website was not service. Called their Manager and he assured technician will visit the next day but no one visited. Each time calling Royaloak Kochi manager was getting same response and no one turns up. Fed up i visited their Showroom but manager was not available. One of the employee listened to my concern and again assured that he will arrange a technician visit and again same no technician visited. After several call, one day the technician called and informed that he can't visit as he has other customer visit. Instead, he assisted me over phone and asked me to send photo of computer chair. After which he concluded that the bottom plywood of the chair is broken and he will inform Manager to do the needful. Manager didn't called back and after i reached the Manager he informed that the chair was damaged because of improper handling by me. How come without visiting and inspecting he concluded about it. I asked him to get it repaired since i reported this within warranty period, else suggest the best possibility to get it repaired. Later he gave me another number (Saying it was number of customer support Manager) and asked me to call to get further support. When i called the new number and started narrating my concern, he asked who gave my number to you ? The Manager shouldn't have given you my number and this is Bangalore number...You should call the same Kochi office Manager and rectify the issue. I waited for 5 months awaiting some response. Now i am fed up and raising my concern here. Hope the concern team from Royaloak will respond.
I am currently using the chair with rope tied (Photo attached).