My eyes are on a different height. What is causing this? (Photo)

Vertical eye/orbit asymmetry is very common among the population, to varying degrees. It is practically not possible to change that asymmetry but some options for improvement are available. Consultation necessary.

Based on your photos, I suspect there is nothing wrong with your eyes themselves.  This is case of facial asymmetry, WHICH EVERY HUMAN BEING HAS!.  None of us are perfect mirror images.  In fact, if you were, you would look strange.  There are many on-line examples of this with celebrities showing how different they appear when made symmetric.  In your case, you do have some slight volume discrepancy between your left and right cheek/right and left face.  Your left cheek has slightly less volume than the right which causes some eyelid asymmetry, and different shadowing between sides.  You would need an in-person consultation and photographs with a board certified facial plastic/oculoplastic/or plastic surgeon to really get to the bottom of this.  However, it is likely that simply adding volume around the eye and cheek with fillers would help with your symmetry.  Hope this helps.

Thank you for sharing your question and posting your photographs. You might have a very subtle ptosis (low eyelid), but not noticeable to me. It might be easier to see in person. Make an appointment for detailed evaluation with an experienced Oculoplastic Surgeon.Good luck,