Getting ERR_NAME_NOT_RESOLVED only from MY PC and only from WIFI

Your DNS settings are wrong.

www.melius.live is an alias for melius.live.
melius.live has address 157.90.29.120
melius.live has address 192.64.119.21
melius.live has IPv6 address 2a01:4f8:c2c:ccb7::
melius.live mail is handled by 20 mx2.zoho.eu.
melius.live mail is handled by 10 mx.zoho.eu.
melius.live mail is handled by 50 mx3.zoho.eu.

You've entered an IP address belonging to Namecheap hosting, and two others belonging to Hetzner. It will be essentially random whether any particular user gets the correct address record first in the list and thus can access your site. I could not.

You should remove the incorrect DNS address record(s) depending on where you are actually hosting your site.