How to link sections to menu items in Bitrix?

Question

CMS

The studio made a website for us, filling it with goods as an example. They created sections and made 2 menus with products: horizontal and left.
I added new products to those that were, but it turned out that when you click on the horizontal menu items, not the products that should be in this section are displayed, but everything in a row, including products from other sections. Simply put, by clicking, for example, on the horizontal menu item "Forms for lanes", all the goods in the heap appear, and not forms for lanes. How to make it so that when you click on a certain item of the horizontal menu, the products of the section of this particular menu item would be displayed?
By the way, in the left menu everything works fine.
Here is the site:
zurmart.ru

Answer 1

if you do not have a zero Bitrix, then support will answer you in 6 hours. Give best practice advice. Take a breath and silently do)

Answer 2

I don’t know about Bitrix at all, but, apparently, the point is that links to the first menu do not add / (slash) to the end.
Alternatively, you can try to search in the code (search by project) for this:

a_lvl1 a_lvl1_boxshadow_top

and add a slash at the end. Crutch, but should help)
Well, or how you find the appropriate piece of code, drop it here.

Answer 3

Now I don’t understand at all: in the morning I went to the site - everything works as it should, although yesterday I tried to fix the problem all day, climbed the entire site. Is this normal for Bitrix?