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Hello to everyone. In the last 2 weeks my website emorroidi.imieirimedinaturali.it has a strange behavior in SERP: it disappears for the keywords ranked and then reappears, and so on. Here's the chronicle of the last days: 12/6: message in GWT: Improvement of the visibility of the website in search. 12/6 the website disappears for all the keywords ranked 16/6 the website reappears for all the keywords ranked with some keywords higher in ranking 18/6 the website disappears for all the keywords ranked 22/6 the website reappears for all the keywords ranked 24/6 the website disappears for all the keywords ranked... I can't explain this situation. Could it be a penalty? What Kind? Thank you.