Someone answered on another forum for me:
"You sure it's whenever you open the door? Or is it when you leave it unlocked? Because what's annoying the crap out of everyone on every forum is leaving the car unlocked in a garage, which constantly notifies you after a few minutes, even though a lot of us have a private garage where it's OK to leave the car unlocked. Hyundai needs to add geofencing to this so that home can be excluded from this unlocked notification.
Anyway, it's under Settings - Remote (in the Notifications section) - Vehicle Current Status Update.
But it will also turn off other updates - not just the "car is unlocked" one. I don't know how many things fall under the "current status update". I've also seen "door is open" (as opposed to unlocked) when leaving it open long enough to vacuum the car."