Windows Phone HTC 8X emergency call problem

[Wiizzard1]

My HTC 8x has developed a really annoying problem when dismissing the lock screen. When the lock screen has been dismissed it randomly says "Emergency calls only". This message is flashed for about 1 second then disappears. After this the phone says "SIM missing" when I try and send a text or make a call. This is a SIM-less phone. Rebooting it fixes the problem, temporarily at least. Does anybody know what could be causing this and what I can do about it?

 

[Laura Knotek]

You cannot make phone calls or send text messages without a SIM. Calling and texting use mobile network, not data, so WiFi will not allow calls or texts.

 

[Wiizzard1]

Sorry I meant to say I purchased the phone as a SIM free phone. It has a SIM. The phone is working and I can make calls and send texts until this problem happens. I then have to reboot the phone before I can use it again.

 

[Wiizzard1]

The problem did turn out to be the sim card after all (I think). I removed it, cleaned it and the problem has not happended since. Strange that it would only show up after dismissing the lock screen though.