2005 Volvo S60 headlight low beam issue

[cah]

I drove Da-Yi to ToysRus at Janss marketplace on May 17 (Fri) to pick up a bottle of formula.
When I started engine preparing to head home, I saw a warning message on the console for S60.
The low beam of headlight was off.

I went to Pep Boys and checked the price for the replacement on May 18. The pack of 2 costs $39.99.
I then checked online and found Sears.com has it for just $23.18. I also checked with AutoZone a few days later and they have the same price as Pep Boys (MSRP price). From all the sources I found. I couldn't get any lower than Sear's so I ordered the bulbs online on May 27 night. They came on June 1st.

Before that, I was checking online for information regarding how to replace the bulb.
One video showed how to do it but the people removed the air filter box to do it due to limited space in engine compartment. I was once trying to fit my fingers in but I couldn't make it. Too many wires and pipes.

I also checked with Victor (coworker) on how to replace it. I was planning to perform the replacement myself but didn't have time this past weekend and plan to work on it the following week since we aren't going to Chino then.

I went to play badminton yesterday afternoon. I didn't pay much attention to the warning any more because I just turned it off after starting the engine. We went to 99 ranch market for grocery shopping and had dinner at Sam Woo BBQ. On the way back, I noticed it is showing position bulb failure but not the low beam.

When I was arriving home towards to the garage, I saw the driver side headlight low beam on!!
No wonder I didn't see the warning message.
Why did it come back to work?! It looks like the bulb is still good. The contact may be the issue then.

Victor also mentioned it might be possible that the fuse was somehow loose.

I prefer consistent symptoms so that troubleshooting is simpler. When this kind of inconsistent behavior appears, it is really hard to troubleshoot.

I will wait and see if it goes off again in the near future.