My garage door has been working randomly. My remote will not open the door sometimes .I did change the battery and thought that was the problem but last night door would not open. I tried several times right outside my garage but no luck. I then tried the keypad. When I entered my code the keypad only flashed and would not open the door. I had to go in the house and hit the button in my garage to open the door. Once inside the garage I tried the keypad and still just flashed. Any ideas? Does this mean someone was tampering with the keypad?