Cancellation, Changes or Reservations, all the things can easily be done via the US Airlines Customer Services for the passengers. You can call on the Airline Customer Services Phone Number of the UA Airline Info and ask for the changes, cancellation and deals, and flight tickets booking. However, this task can also be done at the Website of the airline or through the services of a third party, but you need to do this easily by getting the services of airlines customer support.