Collections not connecting to new landing page

I’ve created a new page “A Guide to Sonic Facilitation”. I copied the Services page as the layout is suitable for my purposes.

The collection currently linked to the new page is from the “Services” Collection. How do I change that to “A Guide to Sonic Facilitation” collection (I’ve only got one in there so far, please let me now if that needs to be more full some).


Here is my site Read-Only: LINK
(how to share your site Read-Only link)