Hi, @Tamer Hossam
Could you please let us know which version of Excel are you using? Based on our test, pivot filter works when using Excel 365. We would suggest you go to Review->Unprotect worksheet to unprotect the worksheet and check the result. If you cannot unprotect the worksheet and you get the workbook from other users, I would suggest you contact with author of the workbook on the issue. For more information on protect worksheet you can refer to protect-a-worksheet-3179efdb-1285-4d49-a9c3-f4ca36276de6
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