Error occured while trying to proxy to: localhost:4000/graphql

Hi all,

I'm trying to start Kotahi project but without success. I've followed instructions in the Readme file, the server starts normally but when I try to request http://localhost:4000 it gives me: {"graphQLErrors":[],"networkError":{"name":"ServerParseError","response":{},"statusCode":504,"bodyText":"Error occured while trying to proxy to: localhost:4000/graphql"},"message":"Unexpected token E in JSON at position 0"}

Any help regarding to this?