I recently adopted the management of our SharePoint tenant which has a classic root. One of the document libraries began having issues with document links not opening correctly. It appears that the creator modified the Document Content Type. See attached image. The Link to a Document also are broken. If you try to get the link to any document in this library and refer to that document in another library it will not work. See image. I don't know what to do to fix this. This site is a Policy Center and has lots of linked documents which stopped working.