What action should be taken if an aircraft is reported at an incorrect altitude?

When an aircraft is reported at an incorrect altitude, confirming the altitude should be the initiating action taken by air traffic controllers. This involves verifying the aircraft's current altitude through direct communication with the pilot or by utilizing radar data. Ensuring accuracy is crucial because an incorrect altitude can lead to potentially dangerous situations, including mid-air collisions or conflicts with other air traffic.

Once the altitude is confirmed, further actions can be taken as necessary, but the first step is to obtain clarity on the aircraft's actual altitude. This process helps to ensure safety and maintain the integrity of the air traffic control system. After confirming, if discrepancies are found, additional instructions can be issued, or advisories can be implemented as needed to resolve any conflicts.