The Auto-Open feature depends on your phone's geofencing capabilities and the first thing to do is make sure you have location services on your phone turned on and set to "High Accuracy" if on an Android phone. On iOS devices you'll need to turn on Motion and Fitness under your phone's Settings - Privacy menu and also turn on Location Services and scroll down and set the setting next to the Nexx app as "Always".

Once that's done make sure you have gone through the "Just Drive" settings in the Nexx Home app and you've set the device location and Auto Open radius - once you're done log out of the app and then log back in. Make sure to drive at least a mile out instead of just driving around the block as the app checks to see if you've left the general location of your garage door and if it detects you haven't left it won't trigger the door.

When driving back make sure you have internet access through your phone's mobile data as the app sends the trigger signal to the device over the internet. Sometimes if your phone is asleep though it may turn off mobile data as well as location services so also try driving up with the phone active to see if Auto Open would work.

​Try setting the radius to the maximum and see if this allows the door to auto open or not.