Collagen in the lips typically only lasted a few weeks. What is left in your lips may be either scar tissue or you were injected with another substance. Consider either adding more filler to improve contour of lips or surgically removing lumps.
From what I can tell in your pictures, it doesn't seem to me that there is a major scar on your lip. Did you have any trauma to the area during or after the injection? At this point, I think whatever may be causing the irregularity you are noticing (and I don't see any in the photo), you'd be...
Goretex implants were once used commonly for lip augmentation and are rarely used currently as they have been replaced by Juvederm or Restylane lip injections. Goretex can usually be removed from the lips using small incisions.