Tell us more.
The FAST says it’s on phase 2
What is the condition of the unit itself?
Doors open? Closed?

On the doors closed scenario, let’s say the building has a fire alarm company check smoke detectors. They check the elevator lobby detectors too. They think they need to check the car operation on phase 1&2. But what they don’t know is on PH2 the car door has to hit DOL and stop motion before releasing the DO button. If they release the button too early even with PH2 keyswitched to “off”, and step out while the door is forced closed, they’re screwed. As they turn the main recall keyswitch to “off or bypass” to reset the “system”, they either notice or don’t the unit is OOS (still on PH2), and they leave. Now you have to get into the cab and reset the sequence...properly. In my career I’ve seen this many a time.
This may or may not be your situation, but the description you give is another probability.