DIAGNOSIS You're in the time-setting mode, which is confusing because the interface isn't intuitive. The blinking means it's waiting for you to input the correct time.
FIX When the clock is blinking, use the 'HOUR' button to advance to the correct hour. Press the 'MIN' button once to move the cursor to the minutes (the hour will stop blinking, minutes will start). Use the 'MIN' button to advance to the correct minute. Then, press the 'CLOCK' button once to lock in the time and exit setting mode. The blinking should stop.
IF THAT DIDN'T WORK A power glitch can corrupt the memory. Unplug the machine for 30 seconds, then plug it back in. The clock will likely flash '12:00'. Now follow the setting steps above from the start.
HEADS UP The clock on these basic models doesn't have a backup battery. If you unplug the coffee maker or have a brief power outage, you'll have to reset the time every single time.