The automatic shut-off function has been activated. It automatically shuts off after 30 seconds in horizontal position and after 8 minutes in vertical position.
Pick the iron up or move it slightly to deactivate the automatic shut-off function, then the red light will stop blinking.
If the amber pilot lamp lights up, wait for it to go off before you start ironing.
For more information, see chapter 'Features' in the user manual, section 'Automatic shut-off'.