post only shows a preview,i tried all, but it does not show the complete post

post only shows a preview,i tried all, but it does not show the complete post. i had the same theme installed but the previous version worked fine, please help. the support of siteground says its a problem of the theme.. thanks in advance. mestesis.apreciamos.com shows just the preview post. apreciamos.com shows the complete post.. why? thanks in advance.