I've tested everything, and every possible way. I already disabled iptables, I did everything myself.
I gave joker permissions on all users and database in mysql.
And anyway, how can test https://cp.nationwarriors.com/ the error persists:
Fatal error connecting to mysql server. SQLSTATE [HY000] [2003] Can not connect to MySQL server on '177.87.231.218' (111)
in localhost I get it. I checked the door is normally open at https://www.yougetsignal.com/tools/open-ports/