I was hoping someone could help me.

I created a new site for a client, now live on the web. Added it to Google etc and Google was picking it up. Up to a week ago I preformed a search for the company name (same as .ie url) and it appeared 4th in Google (Irish Version). I felt this is satisfactory. I have a sitemap set up, robots.txt file etc, all submitted to google.

However for the last week, the site has disappeard from Google when I search. I have no idea of the reason for this. Its seems that google is not indexing the homepage etc. I feel like I have done something wrong or being punished for something, but what?? I'd appreciate if I could get advice on this or could someone give me advice, help me out.

I would prefer not to publicise the URL of the site for the moment.