Hello @fireflywebs,
Sorry for the inconvenienced caused.
We checked in our end, everything is fine. The sidebar is enabled by default for all posts and pages.
And I also checked your site, there you have set no sidebar full width template for all pages from the menu-bar and for the posts you have sidebar there.
Now the case is, if you create a new post and you didn’t get any sidebar although you have set default layout to right sidebar, then your sidebar widget must be empty and you need to add widgets/blocks to the sidebar widget.
And you can also set a different template for every single pages/posts from editor, for that I’ve attached an screenshot.

Hope this helped for you and please kindly let me know for the further assistance.
Thank you.
Regards,
Sujeet