How late can you cancel a refundable United flight

Yes, Changing The Date Of Your :luggage:United:luggage: ????????????????????????????? Flight Is Possible.:airplane: Access Their Official Website Or Call :phone: +1-888 829 1467 (Ota) Or :phone: +1-888 829 1467 (Ota), Their Customer Service Directly.:airplane: Locate Your Booking Under “Manage My Trip,” Input Your Reservation Information,