Nobroker - Deliberately holding refund of subscription

Had put up an Ad in No broker for renting out my property. No broker team chased me a lot to pay-subscribe to their Owner Super Moneyback Plan wherein they will find a tenant or return the money if they cannot find within ** days or I find a tenant with the same terms & conditions as I agree with No broker. Once signed up and paid, their relationship manager came on board with a Whatsapp group. He could not find any lead and I was left to hunt myself. After I found one tenant with the same T&C, I signed up with him and intimated No broker. Thereafter, I had been chasing No broker for the refund since the past * weeks. I had sent * repeated emails, ** phone calls and * Whatsapp reminders. Except for my phone calls, they did not respond at all. For your calls, a new person from 'Relationship Manager Team' respond with sweet positives with verbal assurances that refund will be done within * days, * days, one week etc. However, nothing happens thereafter. I have records of all communication with them.