Land dispute pleasee help really urgent (rural india)

Land dispute after agreement – need advice on next legal steps (India) Hi everyone, I need some guidance regarding a property dispute. This is a real case. I’ve just used AI to help with language and grammar. My family entered into a land deal with our neighbors. The property has three legal owners: a son, his mother, and his sister. All three of them signed an agreement on stamp paper (Agreement to Sell), and we have proof of payment for the transaction. The understanding was that the registry (final sale deed) would be completed later. However, before the registry could be done, the son (who was primarily handling the deal) left home and is currently not available. Now, the situation has changed: The mother and sister are not cooperating fully The uncle (who is not a legal owner and has no power of attorney) is actively interfering and resisting They are threatening to sell the property to someone else within a week We have verified our documents, and everything (agreement + payment proof) is in order. We are also in contact with the village sarpanch, who is aware of the situation and has seen the documents. Our concerns: Since registry is not done yet, how strong is our position legally? Can they legally sell the land to someone else despite our agreement and payment? What is the safest and most effective next step—should we try to take possession, or directly go for legal notice and court action? How urgent is it to file for injunction to prevent resale? We want to handle this the right way without creating any legal trouble for ourselves, especially since a large part of our savings is involved. Any advice from people familiar with property law in India would be really helpful. Thanks in advance