The nameservers listed in the control panel don’t 100% match what’s actually set on the domain, but they ultimately use the same real nameservers. That’s why the Domain Checker tool says all is good.
Please trust us when we tell you that the nameservers of free.nf are fine and nothing to worry about.
And your website is working fine from here. It’s working fine for everyone except for you I think:
So whatever the problem is, it must be something on your end. Could you please check and see if you can access your website from another device or network, for example by using a VPN?