Maintenance ddr

Hello Sir,Ma'am, We are flat owner in a 4 apartment building. There is no such maintenance committee or association formed for maintenance payment and decision making. Everything was based on mutual agreement with the other flat owners. We were not living in the flat so we did not give monthly maintenance but paid for major changes like painting or overhead tank repairing etc. There were some issues with other owners and we didn't see eye to eye many times. So the other owners have filed a DDR against us that we are not paying the maintenance. I wanted to understand do they have any basis to file a DDR when we don't have a maintenance committee in place? We have a sale deed and deed of declaration saying that the building belongs to 4 of us and all are responsible for paying of common area charges. But there is no other documentation. Also other owners have opened a joined bank account but its not in the name of any committee as such or any registered bank account for maintenance payment. Please suggest what can be done in this case. Regard, Pallavi