Did you try the steps in this post? I presume it did not solve the problem. If not…
Next step I would ask you to try would be to remove any other Grasshopper components you may have installed.
These are in:
~/Library/Application Support/McNeel/Rhinoceros/MacPlugins/Grasshopper/Libraries
and see what happens.
What version of macOS (or OS X) are you running?
-Dan