Rule "received update" does not work for item type "Contact"?

I have the following simple rule

rule "door sensor activity"
    Item door_sensor received update
    say("the door has moved")

If I define “door_sensor” like this, I hear the say command.

Number door_sensor "front door" (ALL) {mqtt="<[mqttbroker:frontdoor:state:default]"}

But if I define it as a Contact, I don’t hear the say command.

Contact door_sensor "front door" (ALL) {mqtt="<[mqttbroker:frontdoor:state:default]"}

I’m probably doing something wrong, but could someone point me to the error of my way? I’m not displaying this in my sitemap, just trying to play audio when it happens. And although I can work with the Number type, I’m very confused why the Contact type isn’t working.

maye the Problem is that the contact does not get an update. Maybe it gets a command. so your trigger should something like (Not testet)

Item door_sensor received command OPEN