How can I filter a protected shared worksheet?

I have allowed filtering in protection & can filter the protected worksheet
manually but if I try using vba it says its protected. I can't unprotect then
filter because it's a shared workbook.

You can't protect or unprotect a shared workbook.

I have tried ws.Protect UserInterfaceOnly:=True

Command used to try to filter is:
Selection.AutoFilter Field:=3, Criteria1:="LK", VisibleDropDown:=False

Why can I manually filter not not using the above command.

Regards
Neill