If the keybox flashes a red light after you enter your access code, that means that you entered a code that is either incorrect or has already expired. Make sure that aren't trying to reuse a single-use access code and then follow these steps:
- Press the back arrow on the keybox to clear any previously entered numbers.
- While the keybox is illuminated, enter your access code. Make sure that you hear a beep after each number.
- After you've entered the code, press the unlock button. The keybox should flash a green indicator, confirming that it was successfully unlocked.