This means that the function named is not linked to at least one goal. If right-click Set Exercise Goals does not help and you do not see that function listed with hash marks on your flow sheet, you most likely have a function with that name that was marked as performed and hidden from the flow sheet.
To fix, right-click Edit Flow Sheet. Place a checkmark next to every instance of the function you see there and click OK to make it visible to your flow sheet. Now you should be able to see that function marked as performed with hash-marks. You will either need to uncheck it as performed (if you don't want to charge for it) and then you can hide it from your flow sheet again, or (if you do want to charge for it) you will need to Set Exercise Goals for that function.