According to other threads I've found the LG G3 particularly experiences this very issue which seems to be a manufacturing problem with the "seating" of the SIM card, but I have to say I'm about at my wits end with THIS PHONE!! I've already replaced the micro doc (charging port) on my dime (and NO, I'm not one to be rough on my phones and yank out the cord) and forgo the warranted NOT thinking clearly but wanting it fixed out of desperation, I sent it out thru Office Max, NOW THIS just started!! What gives??!