Rows being deleted unintentionally

Try this:

1.    Use Excel’s Repair Tool
o    Go to File > Open > Browse.
o    Select the workbook.
o    Click the arrow next to Open → choose Open and Repair.
2.    Check for hidden macros
o    Press Alt + F11 to open the VBA editor.
o    Look for Workbook_Open events that might delete rows.
3.    Save a clean copy
o    Copy the “good” sheet into a new workbook.
o    Save the file as .xlsx (not .xls or .xlsm unless macros are required).
4.    Disable add-ins temporarily
o    Go to File > Options > Add-ins.
o    Disable COM and Excel add-ins one by one to see if the issue stops.
5.    Check external links
o    Use Data > Edit Links to see if the workbook is pulling from other files.
o    Break links if they’re unreliable.