In UptimeRobot, team features vary depending on the plan you're on:
Solo Plan: On the Solo plan, you have the option to add notify-only seats. These seats come with one email address and one phone number to be used for both SMS and voice call notifications. The purpose of these seats is solely to receive notifications, as they do not have permissions to manage monitors.
Team and Enterprise Plans: These plans allow you to add both notify-only seats and sub-user/login seats. Sub-user seats can see, manage, and receive notifications about monitors.
You have the flexibility to purchase additional seats at any time from the 'Team Members' page.