I have a similar problem.
The error message is: chirpstack-network-server[940]: time="2021-04-14T15:44:45+02:00" level=warning msg="grpc: Server.Serve failed to create ServerTransport: connection error: desc = \"transport: http2Server.HandleStreams received bogus greeting from client: \"GET / HTTP/1.1\\\\r\\\\nHost: 10\"\""
The search results on the link did not help me. How can I narrow down and fix the error?