I put a 2/3 down payment on my credit card for a Pesach program in Israel. Due to the medical rules, the program is cancelled. Does the organizer owe me the down payment back? Can I negotiate to apply the down payment towards a greater share in next year’s program (e.g. 4/5, or complete) or is it a problem of ribis?
This response is only on a general level and various technicalities can change the result of the answer. For example one needs to see what was written on the contract. One needs to see if there was a “force of majeure” stipulation in place.
Because there’s so many factors that can influence the decision in this case and also because there are multiple opinions on this matter, in the absence of a properly scheduled Din Torah, it is appropriate to reach some compromise between the parties. This is the advice that Batei Dinim all of the world are telling people.
Of course you can try to ask for your money back. However, in order to get a better price for next year, and to avoid ריבית you would need a היתר עיסקא.
See also here (although the principles are not exactly the same):
My child goes to playgroup and we pay at the beginning of every month. Due to the coronavirus… Do I have any obligation to pay?