Byju's — I'm complaining about Byjus Learning Program

On 17/06/21 i purchased the BYJUS LEARNING Program for my sister for standard 4. On 23/06/21 i requested for cancelling of my premium. The mentor's said to gives us few more days then you can cancel it, and we'll give you a discount of Rs13500. Now again i requested for cancellations and they are not responding to the request neither the mentor nor the counselor.
Please Give me Solution what should I do.