pupils don't stay inside eyeball layer - they fly way out of eyeball area

i followed the structure

+Right Pupil

Right Eyeball

--- Does the Right Eyeball layer serve as the mask

*i opened up Chloe

and studied eye structure - she has no clipping masks

it looks like the Right Eyeball layer is the mask for +Right Pupil

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i included a screenshot of my rig and the eye shape

any tips toward solving this much appreciated.. i tried clipping mask but couldn't get mask to activate  - i followed steps..but video was 4 years old

thanks for the help

Taz