Token advance for plot

I have agreed to take a plot on TNHB plots from a owner in chennai. So I have paid 10000 rupees (In cash) a token advance beleiving that I will get approval for two floors as per agents words, and later after 15 days i have paid 1.5 lakhs as advance amount and this 1.5 lakhs is paid in cheque. Now while proceeding with the engineering plan creation i came to know that I will not get approval for 2 floor and now agent is telling sir you can build that by deviation with own money i told i need to take bank loan for complete land and construction loan. so because of the issue i have said i'm dropping this deal within 1 week of making that 1.5lakhs cheque payment and we have a agreement paper for this 1.5lakhs. now I have waited for almost 1 month and they are saying they can pay only if someone else come for buying that plot and they are saying token advance will not be paid back. I totally disagree with that becasue that plot is not on demand first because of my token advance they didn't ignore any other buyer so there is no loss incurred by me first of all. so i want to know what is the legal way of getting this amount back. I have only an sms asking for this token advance apart from this i don't have any recorded proof. So am i eligible to get that token advance of 10k? Expect you opinion on this issue. 10k may not be a big money but this is my first attempt to buy a plot so i want to know about this atleast in future i'll be aware