Is a lip lift the best option for my nonexistent top lip? Additional filler only gives me duck lips. (photos)

I have a small mouth, pretty much NO top lip and a very uneven lip line. I've been getting filler for years and even tried permanent lip liner to address these issues. There is improvement over what I started with, but I've never understood why filler doesn't really fix the problem but causes duck lips instead. I recently learned about the lip lift procedure and am wondering if that may be the best option for me. My philtrum is 2+cm.