Hi @IniobongNkanga-8038,
Before troubleshooting, I have something to confirm with you.
- What's the scope of this issue, One specific Excel file or all Excel files?
- How did users open the workbook? Open in the browser or download and open in local?
Please firstly try Repairing a corrupted workbook and reupload the workbook to SharePoint. If user open the workbook in the browser, also try using a different browser. Sometimes, browser issues can affect how files are opened in SharePoint.
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