If you have Alexa, you can set up a Routine so that when you arm Ring (Home mode, or Away mode), Alexa can lock the door for you automatically when armed. I wanted the same feature, and figured there must be a way. Finally figured out that this would work. The best part is that it doesn’t matter how I arm the alarm system (Ring app, using Alexa, or Ring keypad), Alexa recognizes the system was armed and locks the door if it isn’t locked already.