Setting up door open alert, and turn off monitoring

@herbertyau I use a motion sensor to monitor my garage. Works well even in the cold winters and hot summers of the greater Chicagoland area.  Others have used entry sensors on customized brackets.  (Do a google site search and you will find them).  As far as opened for a certain amount of time, no, haven't seen that with SS but can suggest the Chamberlain B970. Will connect with WIF and they have an app that will tell you when its open and cllosed.

As far as your last question on monitoring, don't understand the question.Sorry; can you provide additional information?

Far as I know there isn't any option with SS to have a notification/reminder sent after X time if you forgot to close the door.

You can, however, look at the individual entry sensor status on the mobile app to see if it shows open/closed, if you have the interactive package.

Simplisafe is a security system that notifies you if a sensor is tripped. It's not designed for that. As someone else said, it sounds like you need a Wifi connected garage door opener to do what you're looking for. We've been very happy with our Chamberlain MyQ openers. We have 2 single doors and use the B550 model. You can set it to alert you when it's left open, when it's opened etc. and check that it's closed from anywhere.

Meross makes a sensor that can do that and also allows you to close or open the door from your phone.