Do any other office applications have the same phenomenon in your Teams client?
Do you mean these specific person cannot view the file normally if files uploaded to Teams channels?
To narrow down the issue, could you provide the screenshot of error message?
According to your description, we assumed that Teams have set the file permission for the specific users and restrict them to open files normally.
As a workaround, you can go to the team members tab and change the user permission to OWNER and then back the MEMBER.
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