Yatra Hotels - refund not credited

I have booked domestic hotel in Delhi from yatra app which I downloaded in Play Store, But due to change in the plan i had to cancel the booking and claimed a refund in bank account and yatra successfully cancelled my booking but it haven't asked me for my bank details or any details to refund the amount, I tried chatting with the customer care and it gives a number for more support but when I tried calling to that number it says the number is invalid and there is no information about the refund and I don't know how to approach them. A common man will face the problem in these scenarios. Most of the people will think they lost their money and apps like these are making money in this way which is completely fraudulent and these things to be stopped as soon as the other common man suffered by the companies like these. I request you to help me to get my refund of rupees **** and also stop companies like yatra do these fraudulent activities with the consumers.