How to grey out a field when a radio dial is selected in another field
I have a field called Customer Type which has three value list options shown as radio dials. The options are Child, Adult, and Agency.
The next field is called Agency Name, which is a pop up list with existing data brought across from another table. However I only want that next field to be useable if the Agency radio dial option is selected.
If Child or Adult are selected, I want the Agency Name field to be disabled. I figured out how to make it white or grey using conditional formatting, however if a user mistakenly populates that field in an invisible way, then that could mess up reports that we want to do, so that solution is not satisfactory.
I think I need to use an If script, but I can't quite work out the formula.
Any help much appreciated.
Best wishes, Tania