Hi @CindyIsabel,
Without knowing the exact steps taken, at some point in time, it sounds like you manually copied and pasted text (including a link to a file) from one course into another course.
That is not something that you should do unless you are certain that students in the first course are also in the other course (unless the first course is public).
To resolve this you should first remove the link(s) to the file(s) and then build them back up again.
How do I link to a document from Canvas in the Rich Content Editor?
I would then recommend that you delete the pages in the second/other course.
How do I delete pages in a course?
You should use then use the "Copy to" option for the page in the first/original course to copy it into the second/other course.
https://community.canvaslms.com/t5/Instructor-Guide/How-do-I-copy-content-from-another-Canvas-course...
Or you can also use the "Copy a Canvas Course" feature with the "Select specific content" option.
How do I copy content from another Canvas course using the Course Import tool?
How do I select specific content as part of a course import?
As long as everything is working properly with how the new link to the file is created, the page and file will both automatically copy/import to the second/other course.
I hope this helps.
-Doug
