Repayment of advance for purchase of land

Hi Sir, I had given an advance of 30 Lakhs for a piece of land worth's around 2.1 crore. Also, we made an agreement for 10 Lakh, in which it was stated that if seller fails to meet terms then he has to pay double of the amount, from the date of agreement signed. Now the seller has some family disputes and he agreed that it will take a long time to resolve that becoz their family members have filed a case against him. Also, he keeps on saying that we refused to take land and we have proof that a case is going on same land and he doesn't have any right to transfer it. Now he is not returning our amount of 30 lacs which was taken as an advance. Everyday he says this and that. Now we have an agreement , and receipts which says that both father & his son has accepted money from us and unable to transfer and the land or repay the advance amount... Please give your valuable thoughts....Also, I have a recording in which they have accepted that they took 30 Lakhs from us and will return soon but didn't as of now.