Create a user in Couchbase Server with the Bucket Admin role, and then update your SG config to include the following fields inside the db property:
"username": "your_cb_username",
"password": "your_cb_password",
This will solve the authentication issue you’re seeing.
As for the empty bucket, check if you have any filters set in the Couchbase Server UI that would be hiding things, and also check the values on the main ‘Bucket’ page to verify the number of documents you have:
