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Hi there, As Martijn has said, I wouldn't worry too much about th DA drop from 16 to 13, there are a range of factors that can affect DA and they're not all within your control. One thing to note in addition is that if you do use the disavow tool from Google to tell them about bad links, this isn't connected to Moz which means that your DA may still go up or down. The disavow tool is good to use if you have links which are clearly bad and that you want to tell Google about, but Moz will not factor this into their DA score. Hope that helps! Paddy