Sterling Holidays Resorts — Want to cancel my membership and want full refund

I have opted for 10 yr membership on 25 July 2022 but now I changed my mind and want to cancel it and want full refund. I have contacted them many times but the only one calling is Puneet Kumar who provided me membership not sterling and he's saying take membership or else they will not give any refunds. They have provided me membership costing 239000 with down payment of Rs 119500 and rest on EMI basis. Pl help me out.