What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
(-23) Aircraft lost left side door immediately after liftoff from runway 10. Before taxi and prior to takeoff, both the pilot and flight instructor claim to have verified the left side door was latched. After the left side door departed the aircraft the flight instructor took control of the aircaft and landed without further incident. Airport personnel retrieved the door and returned it to the on-field aircraft manufacturer.
As the FAA filed it
(-23) AIRCRAFT LOST LEFT SIDE DOOR IMMEDIATELY AFTER LIFTOFF FROM RUNWAY 10. BEFORE TAXI AND PRIOR TO TAKEOFF, BOTH THE PILOT AND FLIGHT INSTRUCTOR CLAIM TO HAVE VERIFIED THE LEFT SIDE DOOR WAS LATCHED. AFTER THE LEFT SIDE DOOR DEPARTED THE AIRCRAFT THE FLIGHT INSTRUCTOR TOOK CONTROL OF THE AIRCAFT AND LANDED WITHOUT FURTHER INCIDENT. AIRPORT PERSONNEL RETRIEVED THE DOOR AND RETURNED IT TO THE ON-FIELD AIRCRAFT MANUFACTURER.