Club Mahindra Holidays - Refund not received

Club Mahindra Membership in the name of Ajay Kumar Madan. I bought a membership in the month of September ****, we didn't receive any call, any mail or any kit till November ****. After visiting their office in Chandigarh we came to know our details (mobile no. and email id) were wrongly updated. Then I get that corrected meanwhile they misguided us by not telling about the annual maintenance charges which near about costs *.* lakhs for ** years and also misguided us that they will offer **% discount on flight bookings (this is not in their policy). Till the time * downpayment of Rs. ***** and *st instalment of Rs. ***** was deducted from my father's credit card. Then we decided to cancel the membership due to their mis-commitments, we received the mail of cancellation on *th December ****, in which it was mentioned we will get the full amount (***** + ***** = *****/-) refund within **-** working days. Due to misplace of the same credit card, we blocked the card and as per the executive request of change of mode of refund of payment (refund through cheque), we have mailed the letter to them (letter attached). After waiting for so long, like it been more than * months we haven't received any call and we haven't received our payment till date. After sending so many reminders through the mail, we haven't received any justified answer of delay and regarding the refund as well. This is very much irritating being the TAT of ** days we haven't received our refund.
I am mailing them again and again but there is no revert from their side. If I call them they straight away tell that it is under process and pending from corporate end.