stop the server and start manually should work.

sure let me know how it goes.

normally in server.cfg you put rcon_password "mypassword"

save the server.cfg file and then stop and start server.

by doing stop and start it reloads the cfg file and your rcon password works.

i think may be plugin is blocking to change rcon . can u disable all plugins and change rcon and see without any plugin enable?

if it works then enable 1 by 1 and finding which making problem

i remember i had this issue before.

i love helping those who needs and give them right solution not go rounds and rounds

God bless you too dear <3