I have two garage door openers, how many GarageDoorBuddy do I need?

When you are working in the garage and the garage door is left open for a long period time, you can silient the notifications from the GDB monitor app if

There is a small hole at the bottom of the monitor, use a pen or paper clip to hold the button inside the hole. When you hear 4 beeps, release

 There is a round hole on the GDB device.  Use a pen or paper clip to hold the button inside for 15 seconds to factory reset the device.  The LED