https://forums.serebii.net/threads/how-do-i-talk-to-delta-airlines-customer-service-step-by-step-guide.781076/
https://forums.serebii.net/threads/accessing-delta-airlines-customer-service-by-phone-email-chat-full-focused-guide.781077/
https://forums.serebii.net/threads/11-ways-to-call-delta-airlines-customer-service-by-phone-email-chat-full-support-guide.781078/
https://forums.serebii.net/threads/10-ways-to-access-delta-airlines-customer-service-by-phone-email-chat-full-focused-guide.781079/
https://forums.serebii.net/threads/ways-to-contacting-delta-customer-service-usa-support-by-phone-chat-direct-guide.781080/