Can't login into the admin panel

Hello,

I setted up a new Ubunut vm just for bitwarden. I installed like in the documentation described. I got access to the userlogin page und the admin panel page, but if i try to login, I get a 504 Gateway Time-out error from nginx.

The registration with a user account is working and I could login.

Error from the log

2021/08/04 07:14:09 [error] 46#46: *2102 upstream timed out (110: Connection timed out) while reading response header from upstream, client: 10.16.1.190, server: 10.16.1.220, request: “POST /admin/login HTTP/2.0”, upstream: “http:192.168.48.8:5000/admin/login”, host: “10.16.1.220”, referrer: “https://10.16.1.220/admin/login?returnUrl=%2Fadmin

enviroment

globalSettings__baseServiceUri__vault=https://localhost
globalSettings__installation__key=fjBgi4Ytbmwfafx8BXkT
globalSettings__yubico__clientId=REPLACE
globalSettings__yubico__key=REPLACE
[email protected]
globalSettings__mail__smtp__host=smtp.gmail.com
globalSettings__mail__smtp__port=587
globalSettings__mail__smtp__ssl=true
[email protected]
globalSettings__mail__smtp__password=password
globalSettings__disableUserRegistration=true
globalSettings__hibpApiKey=REPLACE
[email protected]

Can someone help me?