What is this icon?

[AC Question]

I woke up this morning and checked my phone and i noticed a circle icon.
Its a circle, it has 4 triangles around it and it has some type of shape inside the circle but i cant tell but it looks like a t and the circle has a line going through it.
Does anyone know what this icon means?

 

[Almeuit]

It would be hard to judge without seeing it. Sorry.