Hello...here is the suggestion:
Launch the DisneyNow app and log in to your account using the correct credentials.
Follow the steps in order to get the activation code.
Go to disneynow.com/activate on the device that you want to log in (or the Activate TV option)
Enter the disney activation code on the box.
Click here to know more at: Disneynow/activate | Disneynow activate