Non refund of advance paid to do a project

I paid an institute in Pondicherry an advance of Rs 15,000/- via Cheque to help me with my PhD project. The had committed to complete my project within 20 days assuring that they will give me an progress update every 2-3 days. The remaining amount of Rs 15,000/- was to be paid on successful verification of the completed project. For the advance of Rs 15,000/- they gave me a receipt (where it is written "Cash once paid will not be refunded" - will that create a problem for me?) and also a written confirmation in Company Letterhead that they will complete my project within 20 days. Now the 20 days are over, and they have not given me a single update. They just commit to send an update/video file by "tonight" but that night never came. Since they did not complete my project nor gave me an update in the last 20 days, I am seeking refund which they are not agreeing to. I want to take legal action on them as I took the pain to travel from Bengaluru to Pondicherry twice to meet them apart from the Rs 15,000/- I paid as advance. What legal options do I have?