You can also verify that the External Tool is added in your course. In Course Settings, click the Apps tab . Then click the View App Configuration button .
App Configurations displays a list of all apps in your course. If the desired app is not there, you may need to add the LTI. You may need to reach out to your Canvas admin for help adding an app.
Review External App Documentation
Not all apps display a link in Course Navigation. You may only access some apps from Assignments or Modules or when using the Rich Content Editor. For more information about an app's exact availability and functionality within Canvas, review the documentation created by the application's provider or contact the app support team for further information.