It’s possible that your garage door opener
controller has a “LOCK” function. When engaged by pressing the “LOCK” button for a couple of seconds (usually 2-3) it prevents garage door opener from functioning. Blinking light is a sign that this particular feature has been activated.
If your garage door opener has been equipped with such safety feature push the opener’s “LOCK” button for a few seconds and the blinking light should change to a steady one / opener should become functional again.
If this doesn’t help, write down the brand and the model number of your garage door opener, and forward it to me. Just click “comment” below.