Alexa warn me when it's closed

Create custom workflows effortlessly by selecting triggers, queries, and actions. With IFTTT, it's simple: “If this” trigger happens, “then that” action follows. Streamline tasks and save time with automated workflows that work for you.
9 triggers, queries, and actions
Nice is the smart way to open, close and monitor your garage door from anywhere in the world.
Trigger Alexa Routines and make Text to Speech announcements with Voice Monkey.
Simply enable the Voice Monkey Alexa skill, add a trigger (or monkey) and then use this service to unlock Alexa Routines as an IFTTT Action.
See voicemonkey.io to learn more.