Hi, I upgraded my phone to an iPhone 5c earlier this week, but I've been having an issue where other iPhone users can receive my SMS messages when I'm not on data/wifi but I cannot receive their text messages back (I get the backlog of messages when I turn wifi or data back on). iMessage works fine when I have a wifi/data connection. I've tried everything that I could find online - deleting the message threads, restarting, resetting network settings, deleting the contact entirely and creating them again and even all the fixes associated with iMessage and my appleid. Nothing is working. The only fix I've found is asking the person I'm texting to push through and manually "send as text" on their end. I've had the people I text the most check all their settings and do everything I've done in order to try and resolve this on their end as well but it's just not working no matter what. The strange thing is the day or two after getting this new phone, text messages were sending and receiving just fine... Any idea what I can do to fix this?