How to register a complaint against the housing society?

In Oct 2018, I booked a site in a registered housing society measuring 50*80ft. Upon first payment, I received a Confirmation Letter and Share certificate for membership. The Society's President has been deceptive: Despite repeated asks, they haven't provided layout documentation for legal verification or loan procurement. I discovered there was no planned site of 50ft*80ft after visiting the location in 2022, leaving me unaware for four years. The confirmation letter promised allotment based on seniority, yet I haven't received a site allocation, with few sites available and no updates provided. Despite numerous attempts, they haven't refunded my payment made, despite eligibility outlined in the confirmation letter. Now President is absconding. What steps should I take to reclaim my payment? What legal recourse is available against the society and its President? Can I halt further developments until my refund initiation? Are there repercussions for their deception? Please advise.