Send legal notice through your advocate and can claim refund of amount
Thereafter file petition before Honourable District consumer forum
When you paid the advance did they give some receipt which had any terms and conditions in the backside? If it did, then please read if it has any condition about the refund and cancellation. If it doesn't, then you can send a well drafted legal notice from an advocate and that should get some movement from them to have a discussion with you. If they don't respond to that, then you will have to approach a district consumer forum and they will give the refund.
For any further queries or if you wish to send a legal notice, then you can contact me on firstname.lastname@example.org