LG G3 white rectangular box with x through it in notification bar??

[AC Question]

My mom can't figure out what the white rectangular box with an x through it means? Don't know how to post picture or else I would. It's Verizon so I'm pretty sure there is no Sim card or removeable memory and I've Googled it like crazy and I can't seem to figure it out what so ever!!

 

[belodion]

On which side is it?