When Microsoft Excel detects a corrupted workbook upon opening, it automatically starts File Recovery mode and attempts to repair the workbook. If File Recovery mode doesn’t start, try using this manual process to recover your workbook:

Click File Open.

Click the location and folder that contains the corrupted workbook.

In the Open dialog box, select the corrupted workbook.

Click the arrow next to the Open button, and then click Open and Repair.

To recover as much of the workbook data as possible, pick Repair.

If Repair isn’t able to recover your data, pick Extract Data to extract values and formulas from the workbook.

If neither automatic nor manual repair works, there are some recovery methods that might help salvage your data. You can also take some preventive measures to avoid losing your work by automatically saving a backup copy of your workbook or creating a recovery file from time to time.

Hope this helps. If the issue persists get assistance on https://www.o365cloudexperts.com

Regards,
Jerry