Adding Content Blocks Without Overwriting Existing Content

I’m attempting to add a new content block over the Services section on my homepage, but when I try to add a prebuilt layout to the page, I get this error: “Are you sure you want to overwrite your current content? This can be undone in the builder history.”

I’ve tried adding a row first and then adding the prebuilt layout to that, which I can’t get to work either.

I searched the forums but couldn’t find a solution.

Thank you,