Hi all - just had the same issue on our 2012 Cayenne D. Both left and right.
Solved by changing the bulbs within the headlight module - it’s a H7 spec bulb you need. The instructions to complete this should be in your handbook. Several videos also on YouTube.
When you look at the headlight module it’s the middle of the three bulbs with a right angle reflector.
You have to remove the whole unit out of the body work
Why it doesn’t just say change the bulb I don’t know !!
Hope that helps and works for you too cheers Y