https://community.cyberpanel.net/t/server-initial-configurations-rdns-dramas/53120/4?_gl=164sjnq_gaMTQ3NjEwODAzOS4xNzA2MzQxNDU4_ga_W8T96EDFYG*MTcxNTM3MTEyNC4zNi4xLjE3MTUzNzU2OTkuNjAuMC4w
Solved. by editing hosts. Very thanks for the guide. ^^