Hello Albert,
It sounds like a problem with the immobilizer not being able to read the chip in your key. That's what is the flashing green key means. It would also be likely that the car won't start, although it might crank. This will probably involve getting the car to a Honda dealer at some point if this is the case. The problem is likely the immobilizer or the key or occasionally the ECM (computer) especially if it got wet recently. The ECM is under the dash and if the carpet gets wet, moisture can wick over to it. You should also check both battery terminals to make sure they're clean and tight. Since you haven't indicated there are starting issues, I wouldn't look at the main relay yet. You should make sure to have only the key to your vehicle on your set of keys there could be an interaction with the RFID chip in another key. The three units, Key, Immobilizer and ECM need to recognize each other, and generally only dealers can program this.