Also depending how new the site is Moz Domain Authority score only really updates once a month (ish) next update is due on 24/7. http://moz.com/products/api/updates so you probably wont see any movement until then.
Like mentioned above welcome to the world of SEO where nothing makes sense and can drive you up the walls. Google is a cruel mistress that you won't never understand and are always trying to please.
And have to agree with Andy - never ever pay to go on directories and in honest stay well clear of them, I am trying to get old links removed from these places. A few years ago this was the thing to do to get to number 1 in google and was very simple, now it actually hurts you more in the long run than benefits you.
If you are new you might want to run read this history of SEO as a starting point http://blog.hubspot.com/marketing/history-of-seo-glimpse-into-future-tl-ss