I have two pages:
mainpage.com and reservepage.com

I would like some content from reservepage to be displayed on mainpage, but I don’t want URL to change to reservepage.
I use apache.

Example:

URL:

Here is part of my virtualhost code for mainpage.com:

RewriteEngine On  
        
#Proxy requests for /product to https://reservepage.com/product123/ 
ProxyPass "/product" "https://reservepage.com/product123/" 
ProxyPassReverse "/product" "https://reservepage.com/product123/"  
        
#Exclude specific paths from being proxied 
ProxyPassMatch "^/product/.*" "!"  
        
SSLProxyEngine On

Code works for mainpage.com/product/,
but doesn’t work for mainpage.com/product/about.

On mainpage.com/product/about returns 404 error from reservepage.com.