Everything Is Mess In My Situation

I agreed to buy a plot in 8 Dec 2019 and I paid 1lakh rupees to the seller as advance and I said that I will be only able to buy the property by taking a loan and a proper agreement was made using stamp paper but now I discovered that stamp was of 2009 which I think is not valid. but the problem is now my loan is stuck due to properties GPA so now I'll not be able to buy that land so can I take back my 1 lakh rs or not as it has been nearly one year since I made the deal and the seller is saying that my time is over and he'll not return my money back. If yes then where do I stand legally? One more thing how much it cost to dig up an 8 year old partition deed as the lawyer is asking for 8000rs for the same