linked images changing to clip group images PLEASE HELP

Lately any design I create that involves linking images is causing issues. The designs I create are packaged and shared with outside sources that require all supported images to remain linked to the file, but when I save an AI file all the linked images show as "<clip group> image" and are missing. I found another discussion stating that the reason this is happening is because the AI file is corrupted, but this happens when saving as a new file, updating an existing file and packaging files. No matter what the links disappear. I relink them each and every time, but they do not stay linked. And I know the linked images are not corrupted, because they are used in other designs and function normally and remain linked. I'm at my wits end with this issue. I can't send out anything properly. I need these images to remain linked and nothing I've found or done has fixed the issue. PLEASE HELP!!!!!