There are totally 36 Products in the page and currently 9 products are displayed.
Issue #1 : Sorting and Filter is not working
Issue #2 : On click of Load More Products, it opens in a seperate page and only 2nd Page products are displayed
Deactivate all the third parties plugins not related to the theme and switch to the parent theme. Clean your cache browser.
In order to distinguish which plugins relate to the theme and which do not, deactivate them all and then navigate to Appearance > Install plugins and activate all in the list.