Protecting Sheet stops searching from working

Hello

I have a problem with searching for data when a Tab is password protected
Attached is an example

In Sheet 1, when the tab is not protected, I can search for names by entering a couple of characters in the Yellow bordered cells (A13) and using the handle (small arrow). names containing the characters appear for selection.
When I set Cell A13 to unlocked via format process, then password protect Sheet1, then try to search in A13, search does not work.

Note Range Name Manager contains a formula with offsets etc
Sheet2 shows the Formulae in use

I have tried a VBA password process but still the same situation.
Can anyone please advise how to password protect the tab and still use the search function.