Cant acess my domain in cosmos cloud

i install cosmos cloud, by guide:

install cosmos cloud with local IP. ok.
cosmos cloud installed.

now with domain point public ip, not open.
view logs and not understand, show ip different, but ip point is correctly.

error:
“Bad Request: Invalid hostname. Use your domain instead of your IP to access your server. Check logs if more details are needed.”

i view logs.
install cosmos cloud with local IP (with public IP not open), ok?
and point domain in Cloudflare, insert for record “A” the public IP.
show in logs a IP different. why?