Jira Service Management offers four contact methods you can use for alert notifications:
Email
SMS
Voice phone calls
Mobile push notifications
Each member of your team can add or edit their contact methods anytime through their notifications page. Email address is your default contact method. You can only add two email addresses, two phone numbers for SMS, and two numbers for voice calls at the most. There’s no such limit for the mobile. You can also edit or remove a contact method when necessary.
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