load balancer Best Practice

[ngsecurity]

Hi All.
I've set up a proxy load balancer using nginx to balance queries between two opencti docker container.
the problem is that if i configure all the connectopr and workers to use the BL to connect to opencti it startr give me connection problems and i see the enrichment connector going online and offline. I suspect i've miss some configuration in the proxy but i don't know which one. Wchich would be the BS for this kind of config? attached to this post you could find mine
nginx.txt
default.txt