Condensation in the corner pieces is common and won't hurt anything other than aesthetics.
If the condensation is in the main unit, that's a problem. Moisture will attract and hold dirt and dust, fouling the optics and the inside of the outer lens. The first and easiest thing to check in this scenario would be the two rear covers on the headlight unit. There is one big cover for the main reflector unit with the high and low beam bulbs, and another smaller cover for the fog light bulb. My guess is that one or both is not on right or has missing/bad seals .
This is easy to check and will take less than five minutes.
1) insert the headlight removal tool (5mm socket) with the handle pointing upward.
2) rotate the handle 90° toward the rear of the car. The headlight should have popped loose and slid forward about a 1/4 - 1/2 inch.
3) carefully grab the edges of the headlight that are now exposed and pull the headlight forward gently until it stops, which will be about another 0 - 1/2 inch.
4) with one hand, continue rotating the headlight removal tool toward the rear of the car another 15 to 45° while gently pulling forward on the headlight with the other hand. The headlight should slide out easily from this point.
5) inspect/repair/replace covers and seals and reinstall headlight using the same above process.
If all the seals appear good and the covers are intact, the next thing to check would be the seam between the 2 headlight housing pieces. Also check the entire housing for cracks or defects