Use set variable in place of copy
Use set field with an expression that refers to the variable in place of paste
it would also be a good idea to give your portal an object name and use go to object just before go to portal row to make sure that your script always puts the focus on the correct portal (some future layout change might add a second portal to your layout and you wouldn't want to then have your script suddenly fail to work.)
Using IndivdiualID to identify the portal row seem very likely to fail to consistently put the focus on the correct portal row.
There are ways to do what you want here that do not require having your script interact with a portal.