Https://www.protiviti.com/sites/default/files/webform/students_and_graduates/_sid_/a-complete-list-of-official-unitedtm-airlinestm-customer_r_contact-numbers-in-the-usa.pdf https://www.protiviti.com/sites/default/files/webform/students_and_graduates/_sid_/a-complete-list-of-official-unitedtm-airlinestm-customer_r_contact-numbers-in-the-usa.pdf