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Hi there, If you haven't done anything wrong or spammy in an SEO matter, then you shouldn't worry that much. The first thing that I'd advise you to look for answers is in the previous history of your domain. It's common that old domains have a history of being used in spammy tactics. The second thing to consider is that this is just a private metric, it DOES NOT MEAN that you will have problems or going to be penalized in google search. Then, I'd take a deep read and try to understand what other factors could be impacting your really high spam socre. Here you can find the 27 most important factors for Moz's spam score. Hope it helps, Best luck.