login and register not possible: "Not logged in"

[xep22]

I just installed Hemmelig with docker compose. The login with my user and registration is not possible. I always see a success message for a fraction of a second, then in red "Could not sign in". No error in the log:

{"level":30,"time":1737137340173,"pid":19,"hostname":"hemmelig","reqId":"req-2s","req":{"method":"GET","url":"/assets/index-e8ec8b5c.js","hostname":"127.0.0.1:3001","remoteAddress":"172.21.0.1","remotePort":48152},"msg":"incoming request"} {"level":30,"time":1737137340174,"pid":19,"hostname":"hemmelig","reqId":"req-2s","res":{"statusCode":200},"responseTime":0.8112690448760986,"msg":"request completed"} {"level":30,"time":1737137340178,"pid":19,"hostname":"hemmelig","reqId":"req-2t","req":{"method":"GET","url":"/static/favicon.ico","hostname":"127.0.0.1:3001","remoteAddress":"172.21.0.1","remotePort":48152},"msg":"incoming request"} {"level":30,"time":1737137340178,"pid":19,"hostname":"hemmelig","reqId":"req-2t","res":{"statusCode":304},"responseTime":0.3595600128173828,"msg":"request completed"}

[bjarneo]

Most likely something is up with your setup. What are the ENV variables?