Website Stuck On 2nd page

i am trying to rank of moderate keyword, i manage to grab position on 2nd page but couldn't make to 1st page and i am loosing ranking too

please suggest what should i do to rank on top

what have i done ?

  1. taken authority sites links
  2. Only quality links pointed back to landing page
  3. length of article is 600 words
  4. site is 6 month old
  5. Good onpage seo