I have installed two WordPress platforms (one on example.com and another on example.com/sub).
Both have different themes.
example.com is an e-commerce website and example.com/sub is a blog.
I have set my WordPress Address (URL) to example.com/sub for the second WordPress installation and example.com for the Site Address (URL).
My current URL structure is example.com/sample-post.
When I visit one of my pages (e.g. example.com/blog-post), it sends me to a 404 error page with the example.com theme.
What needs to be done to fix this error?