Charlie can issue three (3) types of certificates:

Certificate of Travel (COT) - This is acceptable proof that the passenger was able to take his/her flight. This is issued after the flight has been flown.
Certificate of Non-Travel (CONT) / Non-Travel Certificate (NTC) - This is issued for when the passenger was unable to board his/her flight, for whatever reason, given that the flight pushed through.
Certificate of Flight Disruption (COFD) - This is issued for when the passenger's flight was canceled or affected by a schedule change.

Certificate Issuance via Charlie

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