I've heard your track and it seems legitimate. Two possible reasons why you were banned:
1.) A moderator sent you a PM asking you for details about your submission and you didn't respond for a long amount of time.
2.) You didn't cite your resources. Particularly when it's your first submission, you need to outline what VST's you used, samples, software, hardware, etc... You submitted that back in the old design which had the "cite your resources" rule literally written above the Author's Comments text box in the submission page so you have no excuse. Moderators usually don't ban for this but it's certainly possible.
I'm currently having your situation checked out but don't be surprised if you'll have to make a new account if you want to submit music to Newgrounds again.