Yebhi.com — Missing Yebhi Coins

In June 2014 I made a purchase on Yebhi but unfortunately that product was not good so I returned and got money in wallet for product and shipping charges that I incurred in sending the product back. But Yebhi got changed so they converted wallet amount to Yebhi coins but that time they didn't converted Rs100 shipping charges to coins and I sent them emails but no response about that. Now few days I was checking my yebhi coin balance and found no balance was there and it showing 0 so sent yebhi email but they are not responding. I was having around 6000 coins but now nothing is showing in account.Yebhi has foodpanda vouchers so how could I have redeemed all of my coins and now they eaten my money.