A group of Microsoft Products and technologies used for sharing and managing content, knowledge, and applications.
Hi Kristin Volsky,
I go through the post carefully, May I know how did the owner share the file with you? User may check permission of who he shared with, I would suggest you find the owner and ask him to check your permission and share it with you again and check the result:
Stop sharing OneDrive or SharePoint files or folders, or change permissions (microsoft.com)
Share SharePoint files or folders (microsoft.com)
Additionally, if you get shared link that require you sign in, to check if the issue related to account conflict in browser, please change to another browser, or open the shared link in InPrivate window of Broswer, or opening share link after clearing browser cache and check the result.
Best Regards,
Clark