@Anonymous User live chat will help you with this.
http://help.nowtv.com/article/Device-limit-reached
Scroll to the bottom and click the blue contact us button. On the next page, click on live chat and explain what happened.
I am not staff, I am a customer that likes to help,
so please click the Thank You/Thumbs Up button if I helped you out and maybe even accept it as a solution? 🙂