Override app templates in theme

I have controller /src/Controller/Product/ProductGridController, and template for him /templates/Product/list.html.twig ($this->render('Product/list.html.twig', [])). Also I have one theme, and I try to override my app template list.html.twig in this theme by /themes/CustomTheme/templates/Product/list.html.twig, but it is not working! How to I can override my template?