https://central.xero.com/s/question/0D58V00009SmZbUSAV/usa-can-i-cancel-my-united-flight-without-penalty

United 𝔸𝕚𝕣𝕝𝕚𝕟𝕖𝕤 allows cancellations within 24 hours of 𝔹𝕠𝕠𝕜𝕚𝕟𝕘 without any fees+𝟭~(𝟠𝟠𝟠)(𝟠𝟚𝟡)(𝟙𝟜𝟞𝟟)., as long as the 𝔹𝕠𝕠𝕜𝕚𝕟𝕘 was made at least one week before departure. +𝟭~(𝟠𝟠𝟠)(𝟠𝟚𝟡)(𝟙𝟜𝟞𝟟). After the 24-hour window