SHM dismiss when disarmed

That’s by design of STHM as John pointed out. If you’re using a ZigBee keypad you could check out this app from RBoy Apps which lets you create your own security system using a keypad to arm and disarm your setup: [RELEASE] Security System: Intruder Alert with Actions - Entry Delay, Exit Delay, Countdowns, Keypads, Lights, Alarms, Pictures/Cameras, Routines