The keypad will display active zones and if it's just picked you up does tell you that zone is preventing arming to make you check you have not missed something
what happens if with the zones for the pirs set to guard access
Enter you code, do you want to arm ( Yes )
Display showing Zone preventing arming Pir?
Then press yes again and leave.
Does it set or not and what happens when you come back in does it (entry) and disarm and show no faults ?