Webshop | SEO | Falling organic positions | Looking for a second opinion

Hi everyone,

I've got this strange feeling I am overlooking some important details which im missing on a project. We've been ranking this website pretty well and some things just don't add up for me. The traffic is going up and so are the orders some categories just won't rank in Google.

For example; A important keyword; loungeset went up from 67 -> 12 in Google. ( this keyword is really competitive, but shouldn't matter ). In matters of days it went from place 12 to 200+ in Google. It took me serveral months to rank this keyword and im just wondering how this could happen. (no manual penalty has been given)

Simalar things happend to other main categories on this shop. They ranked as expected and to places like 11-15 and just dropped back to 200.

Im wondering if anyone experienced the same.

The content + backlinks on this category pages are simalar to competitors in the top 5-20. I got this strange feeling that some of these (keyword) categories should be atleast at place 15-30 in Google atm.

Want more details about the project? Just send me a PM - Also I am willing to pay someone to look deeper into the project with me.

Thanks alot.

Sander