fix link for real

Author: lawreka

api-playground/openapi/setup.mdx

@@ -61,7 +61,7 @@ When using this option, the metadata for the generated pages will have the follo
 
 There are some scenarios in which the default behavior isn't sufficient. If you need more customizability, you can create an MDX page for your OpenAPI operation, and modify it just like any other MDX page.
 
-<Tip>If you have some endpoints in your OpenAPI schema that you don't want pages generated for automatically, you can add the [x-hidden](/openapi/advanced-features#x-hidden) property</Tip>
+<Tip>If you have some endpoints in your OpenAPI schema that you don't want pages generated for automatically, you can add the [x-hidden](/api-playground/openapi/advanced-features#x-hidden) property</Tip>
 
 ## Create MDX files for API pages