Notification bar symbol

[Bob G 49]

I have a samsung galaxy s4.In the notification bar I have an odd symbol that looks like a circle with a horizontal dash in the center of it.When I pull down the notification bar,I don't see anything pertaining to it at all.Can anyone tell me what this could be?

 

[girolez]

Hi

I think that's blocking mode. Normally there is a notification in the drop down.

Roger