ts being one month but but website home page not being cache and internal pages are being cache and ranking well in search engines.
Update XML sitemap of your website & resubmit it in Google Webmaster tool. Also, collect quality backlinks for your home page...
Create XML site map and submit in google webmaster and do analysis through this tool.Submit your home page in high pr social bookmarking site and ping your website in ping-o-matic to cache it. Check your home page website content for duplicay.
You will XML sitemap of your website & resubmit it in Google Webmaster tool and smo activity do it for home page.