If you cannot find a Project ID in the Services Window Settings, or if you observe a mis-match in Project IDs, this may be due to you upgrading a project using an older version of Unity, or by creating a new project while offline. You can remedy this by linking your Analytics project to your project in the Editor.
From Services Window > Settings > Unlink project
Select your Organization and then click “I already have a Unity Project ID”
Find your project in the drop-down, then click “Link” to link your project.