I agree with @Mike-And-Jane0 @Lana1151
I think you are confused. If you cancelled a booking and the cancellation fee was 50% and you only paid 50% of the total cost in the first place then you obviously wouldn't be entitled to any refund
for example
total cost of booking =€200
total amount paid by guest = €100
balance due = €100
guest cancels booking and is charged 50% cancellation fee =€100
you therefore aren't entitled to a refund as you have paid nothing toward the 50% outstanding balance
there is no new cancellation policy . Your refund was processed correctly under the cancellation policy you booked under which would have been shown when you booked .
I can't imagine how you would have a successful claim in small claims court when your cancellation has been processed under the cancellation policy you booked under.
as you had to cancel because of a family emergency have you made a claim under your travel insurance.