Sidebar content missing from some pages on WooCommerce site

I’m a novice and working on a WooCommerce themed site -Mystile.

I’ve set up various widgets in the sidebar, but on 3 pages these widgets are not showing up, although the sidebar space is there, but blank. One page is a main menu item (shop), where the ‘Edit Page’ link is not showing at the top of the page on the black bar. The other two pages are the two product category pages – but the sidebar contents are showing on the main Product Category page.

Any assistance would be most welcome.