NEC SL 1000 Phone Do Not Disturb Keep Flashing On
Do Not Disturb (or also called DND) is a feature that disable ringer. When DND feature is turned on, phone will not ringing once there's incoming calls.
Some of my users saying that their telephone is not ringing for some reason. After some investigation, i found out that the DND mode is activated.
|Do Not Disturb - Source : 58voip.com