2016 expedition alarm sounds when doors are locked.
 

We recently purchased a used 2016 Expedition EL Platinum which we love except for one problem. If you lock the doors and walk away with the fob in your pocket the horn/alarm sounds and only stops when the doors are unlocked. Currently we are leaving it unlocked which makes me very uncomfortable. I tried searching but found nothing. Any ideas how to remedy this situation?

Is there a aftermarket alarm or remote start?
Most likely a door or the hood ajar switch is faulty and the vehicle thinks someone is breaking in.
I believe if you use ForScan viewing live data you can see the reason the last five alarms went off, then you know you need to look at the hood, or left rear door, or right front door, ect.