API returning 502, please help

So, basically, I followed the instructions in the readme and _supposedly_ got all the blockchain indexed and the docker container is running, but I'm getting HTTP 502 when requesting the API and the web app shows this:

Can someone please confirm this app includes the needed API to query the blockchain? it is not very clear.

Tracking the error takes me to the next nginx error log:
```2021/03/18 13:57:25 [crit] 153#153: *59 connect() to unix:/var/electrs-rest.sock failed (2: No such file or directory) while connecting to upstream, client: 46.53.242.215, server: , request: "GET /api/blocks/ HTTP/1.1", upstream: "http://unix:/var/electrs-rest.sock:/blocks/", host: "54.242.81.76:8080"```

Can someone please help me understand what is `http://unix:/var/electrs-rest.sock:/blocks/`? How can I fix this?

Thanks.