Alarm not active

when i set a tag’s alarm , sometimes it won’t acitve.

value > Alarm_h

How to resolve it?

Your screen shots appears indicate that the value has fallen below the setpoint, so naturally its no longer active.
Neverminded, I am thinking of it backwards?

Looks ok to me, SP (alarm_h) is 12 and the tag value is 69.1 which is above the setpoint?

Maybe because Any Change is true?

If true, will alarm on each value change given the alarm mode conditions are met.

Note: This alarm will never be “active” because each active event is paired with a matching clear event, instantly. Available for modes: Above Setpoint, Below Setpoint, Between Setpoints, and Outside Setpoints.