My relaxed lips do not really bother me. However, when I smile one corner seems to droop more than the other. What is causing this asymmetry? Is there a treatment or exercise I can do to fix the droopier side? Ideally a symmetrical smile would be nice but I care more about no longer having the left corner of my smile droop. It makes me look like I'm in pain and it makes me extremely self-conscious about my smile.