These are gate locks.
The lock can be installed in either “fail safe” of “fail secure” mode.
In fail safe mode, the lock requires power to stay locked. If it
loses power, it will not lock.
In fail secure mode, it requires power to unlock. If it loses power,
it will always stay locked.
If it will not lock, see if the lock is in fail safe mode and has lost power.
If it will not unlock, see if it is in fail secure mode and lost power.
Have maintenance check to see if the lock has power.