Run-time error '1004' Application-Defined or object-defined error

Hello friends,

My requirement is to make the cells under Columns Actual, forecast and target (Dimesnion Category) Locked.

I've used various methods like GetOnlyRange but it didnt work.

Now, i've selected all the cells of the sheet, where user can input and made them unlocked. ( from Right-click >FormatCells >Protection tab-->Locked checkbox unchecked)

Then, go to "review" tab, click "Allow Users to edit Ranges", -> Protect Sheet ---> ticked "Unlocked Cells"

Then go to WorkBook Options and set a password for the worksheet.

But on expand, I'm facing Run-time error '1004' Application-Defined or object-defined error.

Please help.

Please help.