There could be multiple reasons for you being unable to register the device. There is few trouble shooting steps that can be conducted with ease at the users end to save time. Ensure that the wireless internet connection is turned on, as you will not be able to register using 3G network. In order to get details about fixing the issues like Fire TV Frozen, then please call the technical support team at 1-800-987-6301, for instant help and get rid from such kind of issue easily.