Manuscript folder is not linked to rest of manuscript

Hi, New to the forum but have been using Scrivener for years. Somehow I have “unlinked” the manuscript folder from the rest of the chapters/manuscript. So when I try to view the whole manuscript or export the whole thing, I can’t. Any ideas how I can re-link it? Tx

Make sure that the chapters are children, not siblings, of the Manuscript folder.

Katherine