Change template & now one of my menu items doesnt work - any ideas what went wrong?

I experimented and changed the template and even though I changed back to what I had originally one of my main menu items does not work anymore.

I am not sure if this is a changed the template issue or a joomla issue.

Can you advise.

Main Landing page > clicked on News main menu item > SHOULD open article News but just hangs and eventually gives an error message.