Error in ASGI Framework when accessing WebUI (Homeassistant addon)

Hi, I have set up the Rhasspy Homeassistant Addon (in Home Assistant OS on a Raspberry Pi 4)
When I try to access the Web interface, I get an Internal Server error with the following error in the log:

Error in ASGI Framework
Traceback (most recent call last):
  File "/usr/lib/rhasspy/.venv/lib/python3.7/site-packages/hypercorn/asyncio/", line 28, in _handle
    await invoke_asgi(app, scope, receive, send)
  File "/usr/lib/rhasspy/.venv/lib/python3.7/site-packages/hypercorn/", line 219, in invoke_asgi
    await app(scope, receive, send)
  File "/usr/lib/rhasspy/.venv/lib/python3.7/site-packages/quart/", line 2053, in __call__
    await self.asgi_app(scope, receive, send)
  File "/usr/lib/rhasspy/rhasspy-server-hermes/rhasspyserver_hermes/", line 305, in __call__
    raise exceptions.HTTPException(404, path,
quart.exceptions.HTTPException: (404, '/', 'rhasspy')

I have no Idea where I went wrong or what is happening. Can someone help me?