Hi, guys i have this site i'm working on and i'm trying to rank some pages in the serps. i have around 60 pages with 800+ words of content on average. i've built backlinks to the main url and now i'm drilling down to the main kws that i'm trying to rank for. so i have this kw with 5600 searches/mth and i used some services in the bst to build links to it. i used the same service on a few lower comp keywords and those are ranked now. but this kw in particular is gone from the serps. i wonder what happened. i've included the image showing the serp action past few weeks. is this a penalty or google dance? if it's a penalty what should i do? should i be worried? thanks for your help guys.