I'll try and get you the info. Essentially, Canreef is hosted on a server along with potentially many other sites. They can all use a single IP or range of IPs. If one of the sites has done something to get added to a spam filter, it would affect all the sites hosted on that server (or farm(collection of servers)). I'm not sure that it can even get adjusted manually if requested, even if the provider was so inclined.
But, we can get you the info and you can forward it (probably
support@yourservername.com) and ask what you can do about it.