When a channel or account is terminated, you'll receive an email with more details about the reason. If you think it happened in error, you can always appeal. Here's more info about account terminations, including why it can happen: https://goo.gl/wi7Ubg . Hope this helps.
Sorry for the time this is taking. We know that some channels are caught up in the review process. Our team is making sure to review all the applications as fast as humanly possible. You should see an update soon in your Creator Studio. Latest update: https://goo.gl/32dvTX