Drone stopped authenticating


I had to change my server because the old one died. I switched everything onto the new server and started with docker-compose, everything is reachable and works fine except drone. Everytime I tried to authenticate I run into following error:
Login Failed. <small>Post "https://gitea.xxx.yyy/login/oauth/access_token": dial tcp connect: no route to host</small>

When I try to ping my gitea instance from the drone container, it works without any issues.

Any ideas?