non blocked domain not loading

So this one is odd. The TLD GLLP.PT does not load when I'm using the service (installed on the UDM-Pro), the log does not report any error or even it beeing blocked, if I use a VPN (with its own DNS servers)I can access it. Same with the cellphone, if connected to the UDM-Pro network it won't load, if I'm using the carrier's data network it works.