Maintenance

I booked a villa and received the allotment letter in Feb 2016. The registration was done in Apr 2017 and handover was completed in Jun 2017. I took possession in Jun 2017. However, the association is charging maintenance from Feb 2017 (as the builder moved out of maintenance of this project from Feb 2017). Is it legal as I took over the possession only in Jun 2017 but I am being charged maintenance from Feb 2017. Construction agreement with builder says: (this is signed by me) The Developer will oversee the maintenance at no extra cost to the purchaser for the first 6 months from the date of delivery of Twin Villa/Independent Villa/House and thereafter it is common date to all Twin Villa/Independent Villa/House for both delivered/undelivered Twin Villa/Independent Villa/House. The Allotte(s)/Agreement holder(s) agree(s) to this arrangement in the common interest of maintenance of the building and it related services that the charges of maintenance will be appropriated for all Twin Villa/Independent Villa/House at one stroke with one start date and end date spanning for period of 6 months. The Allottee(s)/Agreement holders agree(s) to this system of maintenance charges being collected and utilized irrespective of his/her Twin Villa/Independent Villa/House possession given date, and even if the possession is still pending. Can you please clarify if I am liable for maintenance/corpus/capex amount collected before Jun 2017 by my owners association. Thanks