Yes, Ryanair Airlines has a 24-hour cancellation policy that allows passengers to cancel their flights without penalty if the booking is made at least 24 hours +𝟏-𝟖𝟎𝟖-𝟕𝟓𝟏-𝟐𝟐𝟔𝟐 (𝐔𝐒𝐀) 𝐨𝐫 +𝟒𝟒-𝟐𝟎𝟑-𝟗𝟎𝟎-𝟑𝟎𝟎𝟗 (𝐔𝐊) before the scheduled departure.

https://www.devex.com/people/ryn_refund_policy-does-ryanair-have-a-free-cancellation-period-2085447