https://flying-guide-customer-support.uvdesk.com/en/blog/delta-airlines-customer-service-via-phone-chat-and-email-a-step-by-step-guide
https://support.google.com/admanager/thread/333822952?hl=en&sjid=13431230271905998108-NC
https://www.steadyhealth.com/topics/8-ways-reach-etihad-airways-customer-service-phone-email-and-chat-options-explained-contact-guide
https://support.google.com/edu/classroom/thread/333312776?hl=en&sjid=8120120475251888246-NC
https://support.google.com/phoneapp/thread/332657659?hl=en&sjid=13844426891012086869-NC
https://support.google.com/phoneapp/thread/331674929?hl=en&sjid=11556445859613669644-NC
https://unitedhelp.helpshift.com/hc/en/3-my-app/faq/79-delta-airlines-customer-service-a-complete-guide/
https://myexpedianews.helpshift.com/hc/faq/11-expedia-cancellation-policy-855-564-8074/
https://www.steadyhealth.com/topics/delta-airlines-customer-service-phone-support-for-international-calls?register_modal=1
https://support.google.com/admanager/thread/329235888?hl=en&sjid=3065768799706805378-NC