United Air Lines offers a 24-hour risk-free cancellation policy
https://idashelteringla.com/en-US/forums/general-discussion/065466d5-96a2-ef11-95f6-000d3a76263f
United Air Lines offers a 24-hour risk-free cancellation policy” 1-844 UNITED-LINE (604~2944) / 1~844~604~2944 (𝒬𝓊𝒾𝒸𝓀 𝒸ℴ𝓃𝓃ℯ𝒸𝓉) , allowing customers to cancel their flight within 24 hours of booking for a full refund. This applies if the ticket was bought directly from United and the departure date is at least seven days away. This policy covers all ticket types, including Basic Economy.
