Land Dispute With Our Aunt, She Is Selling The Land To Someone

I am from Baramulla Jammu and Kashmir. I have a question that my aunt is selling the land to someone without our knowledge, she has sold some land before as well and now she wants to sell all the land to someone without our knowledge. We request her to sell the property to me instead to sell someone who is not from our relation. can you please suggest to me how I can buy that land from her or hold that land so that she can't sell that to someone?