A systemd service name belongs to a manager, and an enabled unit is not necessarily running now. Before starting or reinstalling a desktop component, identify the expected scope and read its current state. A status check can often explain why two apparently contradictory observations coexist.

Ask the correct manager

Obtain the exact unit name from the application's documentation or its administrator. For a system service, inspect it with systemctl status followed by that name. For a service belonging to the current user's manager, use systemctl --user status with the documented name while signed in as that user.

A missing unit in one scope does not prove that no corresponding service exists in another. Adding sudo to a user-service command can change the account context and make the investigation more confusing. Keep the account, scope and exact command with the captured result.

Read the Loaded line and the Active line separately. Loaded describes whether the definition is available, with associated enablement information. Active describes runtime state and its more specific substate. A failed result should include the recorded reason or recent messages, not just a red indicator.

Compare status with expected behaviour

Enabling a unit arranges its activation relationship; it does not, by itself, start the unit immediately. Disabling it likewise does not inherently stop an already-running instance. Some components are activated on demand, so a stopped process may be intentional when its feature is idle.

Compare the result with the application's documented operation before proposing a change. Preserve recent error messages before clearing failure state or repeatedly restarting anything. A component used by several applications may have a wider effect than the one visible window.

If an administrator makes a justified correction, repeat the same scoped status check and then test the desktop function that originally failed. A green service state alone is not application acceptance. Record both the manager's observation and whether the user can complete the intended task.

Sources: Ubuntu documentation.