There could be a few potential reasons why the face rig is not deforming the mesh properly in your character model:
- Check that the vertex groups are assigned correctly to the different parts of the face like mouth, chin, cheeks etc. Make sure vertices belong to the right groups.
- Ensure the groups have the appropriate weights painted well. There should be a smooth falloff from 1 to 0. Blend and tweak weights if needed.
- Verify the rig bones and controls are linked to the proper vertex groups and have sufficient influence.
geometry dash- Test basic shapes like smile/frown to see if certain areas deform more than others. Adjust weights accordingly.
- Pole targets may need adjustment to get better curvature around the mouth and eyes.
- Increase deform axis divisions in rig settings for finer deforms.
- Apply corrective smooth/linear meshes or shapekeys for mouth and eyes.
- Retarget existing working face rigs as a test. See if issue persists.
- Check for face topology issues, uneven edge loops may cause poor deformation.
Without seeing your specific blend file, it's difficult to pinpoint the exact cause. But going through deformation troubleshooting like above should help identify and fix the problem. Share some blend files if still stuck!