Hi Tina. You can mark roadblocks or "brick walls" with a category. Have a look at
https://www.wikitree.com/wiki/Category:Family_Brick_Walls
For the profile you mention, you would need a category "Johnson Family Brick Walls". That one doesn't exist yet, but you could ask for help in creating it by editing the profile and on the right hand side of the edit tab, under the heading "How to Create Categories", clicking the link request a new category or advice and submitting the resulting form.
Hi Rick. The profile I linked link I gave is a mid-level category. It's true that profiles are permitted to be placed directly into it when there is no surname category available. But that makes for an excessively large category. It's better to differentiate by surname and add profiles to the narrowest category possible, as the instructions on the category page say, and also according to a general WikiTree principle.