https://forums.serebii.net/threads/step-by-step-guide-to-contacting-delta-airlines-customer-service-by-chat-email-and-phone-direct-support.781092/
https://forums.serebii.net/threads/ways-to-call-delta-airlines-customer-care-service-us-via-phone-chat-and-email-an-explained-guide.781093/
https://forums.serebii.net/threads/ways-to-quickly-call-delta-airlines-customer-service-via-phone-chat-and-email-an-explained-guide.781094/
https://forums.serebii.net/threads/ways-to-directly-contact-with-delta-airlines-customer-service-via-phone-chat-and-email-a-complete-guide.781095/
https://forums.serebii.net/threads/ways-to-reach-to-delta-airlines-customer-service-via-phone-chat-and-email-a-complete-guide.781096/