To file a complaint with Delta, contact their Customer Care team at +1-(877) 350^????????????????or+1-(877) 350^????????????????You can also reach them via chat support or email. For serious concerns, consider reaching out through social media or disputing the charge with your bank if a refund is denied. https://community.otofonix.com/forums/discussion/experthelp-how-do-i-file-a-complaint-with-delta-2/