Sony Z3,🚫 symbol showing on top bar?

[Symbol]

There is a symbol on the top bar, 🚫 what does it mean?

[Uliwooly]

@Symbol

on the home screen press the volume key and tap on Sound 

[Uliwooly · Accepted solution]

@Symbol

You can read more about new Lollipop features here

http://talk.sonymobile.com/t5/Software-Updates/Lollipop-New-Features/m-p/955490#U955490

[_alexdon_]

The symbol means no interruptions.