Facet search by category doesn't display all products - it is fixed after refresh

[Cytrynka46]

Hello,

I use facet search to enable filtering products by category. Recently I added new product to category "Orto" - it is configured the same way as others.

1. Facet search displays Orto(6).
2. When I select Orto checkbox, it changes to Orto(5) and display only 5 products, without the newest one, which also belongs to category. Order of the categories is mixed.
3. After refreshing page I see again Orto(6) on facet search and all 6 products. Order of categories is correct again (by name).

I tried:

• change category of the product to Y and back to X
• clear cache in facet search module
• rebuild index in facet search module
• enable and disable cache in facet search module
• upgrade facet search module
• clear browser cache

I use:

• facet search v2.2.1 
• Prestashop 1.7.4.4
• PHP 7.1.33

Is it a bug? Can I do something to fix it?