Content preview not working for the local environment


I am trying to fetch the content from javascript which is working fine, but I want to preview my content for the local environment. For that, I have set up a new preview for my local environment and connected to the content type.

The problem is whenever I clicked on the open preview it always shows me the published
content. I always need to publish the content for the preview.

Just to inform, I am using a free account, Is it due to this reason or something else If anyone can help it will be really helpful

Check out this link about Setting a default preview environment.