Add "active" class to navbar if on the page

What’s up dudes, I know there were similar problems and threads here about “active” classes in navbar, but I’m doing everything properly (as in those threads) and still my navbar is broken. Can somebody help me?

in my config.toml:

[menu]
[[menu.main]]
name = "O firmie"
weight = -110
identifier = "about"
url = “/kim-jestesmy/”
[[menu.main]]
name = "oferta"
weight = -100
url = "/oferta/"
identifier = “oferta”

my navbar partial:

{{ $isPage := . }}
{{ range .Site.Menus.main }}

<li class= "nav-li" >
<a class= " nav-a {{if (eq .Name "Kontakt") }}nav-cta{{end}} {{if or ($isPage.IsMenuCurrent "main" .) ($isPage.HasMenuCurrent "main" .) }}active{{end}}" href="{{ .URL }}">
{{ .Pre }}
<span>{{ .Name }}</span>

{{end}}
</li>

What’s wrong with that? Thank you!