Sorry to hear that your husbands new phone has an error of device not registered when trying TV Anywhere.
When you get chance on your laptop, sign into your account, under My Profile select Device Settings. In here you should see the devices already registered to use TV Anywhere. Remove one of the devices that you no longer use. Then on your husbands phone, go into the TV Anywhere app, select a stream-able channel which will prompt you for registration.
Fingers crossed this works for you. Let me know how you get on.