301 Redirects - But still duplicate content?

[Taulia]

Our website domain website.com redirects to website.com/en (since it's in English). Therefore, all pages on website.com redirects to website.com/en.

In my Moz analytics, it says I have duplicate content, and lists all of these pages. Didn't the 301 redirects take care of the duplicate content? Or do I still have to add canonical tags?

[Chris.Menke]

Taulia,  the duplicate content indications that your Moz campaign shows for pages that have been 301 redirected are there so you can make sure your redirects are targeting the right page.  They're not actually errors and no, you don't also have to use conanical tags to those pages.