I can't add ringback tones. I have a Verizon LG3. On the online Verizon website page where you want to purchase the ringback tone of your choice, after you click on Buy, a window pops up where you have to enter either your user id or phone number. No matter whether I enter my user id or my phone number, this takes me back to the purchase page. It's an endless, circular loop. (Yes, my device is registered.) What's the problem?