WebSocket connection Error

When I clone repo, npm install, and npm run, I get the following error:

'WebSocket connection to 'wss://https//yelp-hasura-app.herokuapp.com/v1/graphql' failed: Error in connection establishment: net::ERR_NAME_NOT_RESOLVED'

My GraphQL tables are working, and I can make queries on Hasura. Any idea why I am getting this error? Thanks for any leads, and - great tutorial! :-)

Start by running the cloned app with npm install and npm run, then inspect the configured WebSocket endpoint associated with the GraphQL connection. Compare the generated endpoint with the reported wss://https//yelp-hasura-app.herokuapp.com/v1/graphql URL; done means the connection no longer fails with ERR_NAME_NOT_RESOLVED.

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