Thanks for you reply.

Yes. The slide title in the original ppt is showing as Title 1 in the selection pane and the title placeholder of the new template is also showing as Title 1 (and the title option is selected in its slide master).

And after I apply the new template, there are now 2 Title 1 fields showing in the selection pane (the blank placeholder one from the template and the title text from the original ppt).