Yes they have now got back to me and said the ip changed over night to

145.239.136.178

Is there any way you can fix this for me?

There is no way to update the IP address of a registered server.
Additionally there is no way to transfer server rank.

You may wish to delete the old server page, and add the new one, or you may wish to use the dns host name option as explained in the second part here;
https://www.gametracker.com/forums/forum.php?site=1&thread=108256

Note that by using dns, the server may take up to 24 hours to begin scanning. It is usually less, but that cannot be promised. The process is entirely automated.