We'd like to know more. Could you share the channel URL? Also, visit here: https://www.youtube.com/features > Monetization and send us the screenshot of the page that you see. This would help us look into the issue better.
If you were eligible & applied before June 1st, then you should have received an email & update in Creator Studio w/ more info. If your application is being held for an additional review, then you'll get a second update in the near future: https://goo.gl/2icqfh 2/2