npm to another container on the same docker

[stanthewizzard]

Hello

I have NPM on 192.168.0.35
working perfectly for everything outside this IP

nextcloud is on the same docker
On NPM i have added nextcloud network
i can ping inside npm container nextcloud-web

I have a rule
https nextcloud-web 5011 (link to 443 for nextcloud)

Doesn"t work

If I shut iptable and replace nextcloud-web by 192.168.0.35

What am I doing wrong ?
Thank for help

EDIT:
need to have a common network between the 2 containers
then nextcloud-web internal port
it works