By default, a team leader can only request feedback from someone about their own team members. As an admin, you can also give team leaders the ability to request feedback about someone outside their team.
To enable this setting, first navigate to Studio > Feedback
You will now see the feedback settings screen. If you scroll to the bottom of the page, you will see the option “Allow team leaders to request feedback for”. You can toggle this setting to the option “All people” to allow team leaders to request feedback about any user outside their team. After doing that, click on the “Save changes” button at the top of the screen: