Why my car head light are flashing in the middle of the night

What is your question?

When my car is park in the driveway and you can see my car headlight flashing , the light turn on for 10 second then it flash three or four time then repeat again after 20 minutes , do that 4 to 5 time then stop, it do that every few days , I saw that most of the time at night but I been told that people saw my car do that in day time too , Thanks for your help