Hello. I usually build 1 PBN to my money site each month. On 16th November average position for my keywords was 15.5 and on 16th November I drop my third PBN backlink to my money site. My site's position started to increase. On 22th november average position for my keywords was 12 and I hit for the first time the position #12 for my main keywords. But after that day my site has started dropping position. Actually my site is turned back at position #16 for my main keywords. And average position for my keywords is 14, and every day is slowly dropping. Why? What I did wrong?