Will I get refund? If possible what should I do?

We are from Coimbatore, Tamil Nadu. My mother agreed to purchase a 8 years old house from a reseller. Since the house was unoccupied for past 2-3 years, it had some repair works. We finalized for 38 lakhs and payed 6 lakhs as an advance amount by signing agreement and rest will be paid from home loan. Once after house documents went for verification process by bank we came to know the building was build for minimum square feet of 873 than mentioned in building approved plan which was mentioned as 1023 sq.ft. Also the valuation done and given to the house and land by bank was for 35 lakhs only. Now we are very upset not willing to step further for purchasing the house. But, in sale agreement there is a clause mentioning that "money can't be refunded if the sale is incomplete by the buyer within a month". Now, my doubts are: 1. Since we mentioned we are not going purchase the land, can i get refund of the payed advance amount? 2. Is there any possibilities to mention the point that building sq.ft measurements are not the same one that is mentioned in agreement?