If you are a Teamflect administrator, you can find this button in the lower-left corner of the app. With the Admin Center, you can make important changes at the backend to adjust your end-user's experience within the app.
To open Teamflect Admin Center, simply go to https://admin.teamflect.com or click the "Admin Center" link located at the bottom left of the screen.
If you don't have admin permissions, this button will not be visible to you, and also you won't be able to log in to the Teamflect Admin Center by going to https://admin.teamflect.com.
Note: If you want to have access to the Teamflect Admin Center, you need to contact one of the existing admins. To do that, please see this article here.