I only have mine set for 4 apps in addition to the phone...Messages+, Gmail, Reminder, Voicemail.
The only thing working now is a call and Reminder.
Phone: screen off, face down. With the phone's Edge Lighting, you can't choose your color or style
Messages+: no
Gmail: no
Voicemail: no
Samsung's Reminder (that I never use because I Google Homes that use Google Assistant) : screen up, off...yes.
screen down, off...yes.
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Which of your Edge Lighting alerts are working?