Builder not paying back money

I booked a house in under construction project In bhilai by Shri Balaji builders . It was independent house project . We did an agreement on [deleted] for this I paid 4,31,000. After this lockdown was there so I couldn't visit Bhilai as work in Visakhapatnam . After flights train services normalised then I thought to move ahead with the process . But i was not getting reliable response from them . Then I decide to visit Bhilai . When I reached there I came to know that the Land has some issues and it has been sealed . Then I asked the agent of Builder then he accepted that some issues are there and they are trying to resolve . But earlier they told that some registry has been done , loans has been cleared in that project . Obviously those were lies of agent. I asked them to cancel my booking and return my 4,31,000 back . In November but after frequent follow-up the Builder has paid back 2 lakh . Now he has stopped picking my call and not replying my messages . What are the legal options I have . And what interest on my money I should claim from the Builder and since when . Since March or since I cancelled the property .