Zestmoney — Not receiving Interest Cashback on no cost emi

I have purchased Redmi note 12 5g on Sep 7 2023 for the amount of 13.5k on 8 months of No cost emi and as per their policy I was supposed to receive the interest amount as cashback after paying the emi dues ...it's been more than 4 months now and I haven't received any cashback for last 4 emi I've been my dues on time..tried contacting their customer support but no response emailed them 4 times still no response from them