Error with Nexcloud 20 docker ngrix reverse proxy

Hi, I;m using nextcloud from the beginig, but this is the first install with docker and using reverse proxy with ngrix. So I’m having a few problems, for what I read the are all tie to ngrix reverse proxy. But I don’t fully understand it yet. So plase so help and patience.
Before asking, Nextcloud 20 (apache is working, I can connect using my web addres without problem.
But I can’t connect is I tried to use my local server ip, i get " 503 Service Temporarily Unavailable"
Second I for what I read, is relate. I can give accese to app using token. Neither windows app nor Andorid app. Windows app open a web broser page where i give accese para it get stuck there.
Android app give a message saying the token state do not correspond. Or something like that.
Thanks