Create a database, user on a stolon cluster

I have successfully installed a stolon cluster on a kubernetes cluster using the examples, but when am trying to create a new database, user and grant permissions to that user in a kubernetes job, i keep getting this error:

psql: error: connection to server at “XXXXX” (XX:XX:XX:XX), port 5432 failed: server closed the connection unexpectedly
This probably means the server terminated abnormally
before or while processing the request.

Am stuck. Please help.