I had exactly the same problem. From some e-mails and calls to web-based and local vendors, I discovered that I had put the system into a locked or "vacation" mode.
I have a one-button system, a toggle switch, not a multi-switch system some vendors referred to. However, I simply pressed and held the button for a couple of seconds after the door began to open. The light changed to a steady green, and I was able to use my remote.
Ironically, I was not able to set it to vacation mode again.
You may have to experiment with which end of the button to push and how long to hold it down. I don't know if it makes a difference, but I pushed the end opposite the ridges. Your buttons may differ.