How can I enable persistent notificatons?

Persistent notifications are sent as long as a signl alert is not acknowledged and confirmed. Users can choose which way these repeated notifications should be sent: Push, SMS and Call. The interval can be configured.

Persistent notifications must be explicitly enabled for each team in the team settings: https://account.signl4.com/manage/TeamSettings

Additionally, each user can select their preferred 'nag' channel in the mobile app.