I'm worried that my smile might look awkward.

I am considering getting wrinkle fillers because the deep marionette lines running down both sides of my mouth make me look tired and depressed. They are also known as "pout lines." However, I’ve heard that since the area around the mouth is highly active with a lot of muscle movement during meals or conversations, fillers can easily clump to one side or the injection lines can become visible over time. I am getting increasingly anxious about the possibility that the filler might harden or clump, making my smile look awkward... though I do want to get the procedure done. For those of you who have personally received filler treatments for marionette lines or wrinkles around the mouth, did it look natural when you made facial expressions, and did the effects last a long time without any foreign body sensation or clumping?