Already happened to me three times where suddenly "preparing sim card" appears and I lose signal. Had to hard reset all the time. Unfortunately, htc shops here in the Philippines are crap. They say they have to send it to service center even if the phone is a week old. For what? So they open it up? I don't want to have a week old phone opened and fixed. I want a replacement.
HTC Butterfly(X920d Unbranded)
ROM: Virtuous 2.0.0

Nokia Lumia 920(Unlocked)
OS Version: Portico