I have a trigger that sometimes works just plain wrong. Most of the time it works well, but every now and then it'd fire without any reason.

Trigger expression:

{Template_app1:executors.max(3600)}<7 & {Template_app1:job_queue_length.max(3600)}>50

Action message:

{TRIGGER.NAME}: {STATUS}
Executors number: {ITEM.VALUE1}
Queue length: {ITEM.VALUE2}
Event ID: {EVENT.ID}

(I have also tried "

", it doesn't make any difference)

Actual received message:

App1 is missing executors on srv20: PROBLEM
Executors number: 0
Queue length: 1
Event ID: 3138872

That just shouldn't be happening, should it? I checked the graphs, checked values in the database directly. The notification is correct, the trigger shouldn't have fired.
Both items are Numeric(unsigned), Decimal.