Problem with DNS, blog offline

Hi would be great if someone could help with the following.

I few days ago my blog went offline for no apparent reason.

Then I went to store section and it said DNS needed to be updated. Not sure why.

My domain name is registered with Fasthosts, so I logged onto there to check the nameservers.

Under the ‘My Domains’ section of wordpress it said:

‘Point tomgrant.org’s nameservers to your site

Using the DNS tools provided by your domain registrar, remove any existing nameservers and add the following:

NS1.WORDPRESS.COM
NS2.WORDPRESS.COM
NS3.WORDPRESS.COM
Then come back here and try again. It may take several hours for our system to recognize the changes.’

But the nameservers for my Fasthosts account already were the correct wordpress nameservers it is asking me to change them to.

Nonetheless, I re-entered the nameservers in Fasthosts and updated.

24 hours later it is still not working and WordPress is still telling me that ‘We checked the nameservers and it looks like they’re not pointing to WordPress.com yet.’

How is it they are not pointing to WordPress?

Any help would be really appreciated!

Many thanks

Tom