I've been having many problems with my phone for the past few days. On Saturday, my phone displayed an Invalid Sim message. I restarted my phone, and it ended up showing a No Sim message. I waited until monday to go get a new sim card, because it had moments where it would suddenly start working again. It's now Tuesday, my sim card and phone have been working perfectly fine up until right now. Suddenly, my iMessage stopped working. It constantly says "waiting for activation". It's linked to my apple ID, and my email is checked off, but I cannot check off my phone number to send and receive imessages from my phone. Any advice/tips on fixing this?