xenon fog light

My friends car has xenon on the fog lights. Today, I realized that the light intensity of one is normal, while the other is a little more pale.

There may be a lack of contact or a drop in the bulb's value? How long have you used xenos?

I have the same problem, I bought 6000k xenon, it's been 2 days, there are light yellow patterns on the right side, there is no left, I got a zero guaranteed closed box.

I think it's been 3 years ..

It was affected by water or other factors over time.

Is it possible to repair? or need to change it?