Also, so far they have not identified the problem with the hinge, so it's time for diagnosis, redesign or requalify and possibly fabricate and retrofit, which could all take a while.
It's not as if it was obvious, or anything like that, that designing a jet with a whole bunch of doors exposed to rapid airflow, noise and vibration, that have to close to tight tolerances after take-off, and are all flight-critical on landing, might be a challenge.
So much for rigs, modeling and simulation, and tests being purely validation.