Foreign SEO site being Stuborn

So basicly I have a german site built in the same method as my other English sites which all rank, but this thing won't rank well most of my key words are on page 2-3 on terms that look easy to rank. I hit with 10 PBN posts 4 spread on the home page and the rest on 2-3 inner pages and about 40 web 2.0s. Most of the search terms around 300-500 and low competition around 24-29 from keywordfinder. Really weird, its been a 4 months since I created the site and started hitting with web 2.0s and pbs last month? Should I keep waiting for it to get a surge in rankings or is this sandboxing, not ranking well?

I'd suggest you to check your on-page optimization first and then check what backlinks the other sites are getting.

If you are using local targeting, then better to get or make back links from localize!

The Best Way Is Analysis Your Competitors Or Top 10 Results !

Try to post some content on sites and use some social media's. Also check with all onpage stats like title tag, mobile optimization, page speed etc., update your sitemap. Check with your competitor's strategy on that keywords and try to implement it