Sometimes when I closed my garage door use the remote, the door comes down a little bit then go up and the opener light flashing. I only can hold the wall swith to close it. But after a couple of hours later I can use remote open and close. It's very stranger. Few days later the same issue comes back. How can I fix that problem?

Something is either breaking the light beam across the door or the sensors are not properly aligned. Check alignment of sensor and insure that they are stable. Had a situation once where the rope for manually pulling the door down would occasionally break the light beam just before it completely closed. Didn't happen every time. Had watch it close several times.

Have had the same issue at our church. The sun would shine across the concrete, hit the sensor and cancel the beam. We had to block the light with a piece of cardboard. 1 hour later it was fine. Look for spider webs, leaves etc. in the beam.