How to Reboot Your Product
Some LED Drivers have a Protection Feature which serves the function of protecting the electronics in the driver in case of events such as Over Voltage, Short Circuit, and Over Temperature.
Some Drivers simply limit the output until the event is back to normal and then they auto recover. While other drivers will shut off completely in order to protect themselves from permanent failure. This feature prevents damage from occurring to the driver. Most will auto recover when the fault condition is removed.
Other times, you may have to reset the power cycle by completely shutting off power to the luminare. Upon power reset, the light should be back to normal.
This may not always be a simple solution. But it is worth trying before making the assumption that the fixture simply failed - and then having to get a lift to remove the fixtures and send it back.
It may also be worthwhile to bench test the fixtures before shipping them back.