Hi @Nguyen, Tee ,
To narrow down this issue, I have something to confirm with you. Can you open file in office word client via File -> Open -> Browse -> access your SharePoint library instead of opening directly in SharePoint site? Does this happen with all word files or only some? Do all users in your farm have trouble with this issue? Will change a browser give a favor to you? As per my research, it seems not to be a problem with SharePoint. It was either caused by authentication system (ADFS) or Office. Tell the issue users to reinstall office and see if it will solve this issue.
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