You actor should only speak to the voice clip in that actors voice clip track.
Make sure your voices are in separate recordings, not the same one placed in both actors track (although it can be done but more work).
Facial mouth sprite changes (i.e. angry) override the lip phonemes. You must release the mouth sprite before the lip phonemes will be active again.
Loop in the actors Face tab and expand the Voice track. There you will see the Lip phonemes where you can move, delete, and add the lip phonemes.
Under the Face motion track select the Mouth option to show the mouth sprite (Mouth_S) changes that might be overriding your lip phonemes.
Jeff
Get my Plugin Manager and TaskNotes plugins for iClone.
Check out EZColors and Other products for CTA/CA. EZColors: the easy way to change Render Styled (RS) colors!
See my CTA Tutorials on the YouTube channel CTAStepByStep