What does this crescent shaped icon mean and do? This icon popped up on my screen today. I don't know how or what it does and how to remove it. I have a Redmi 4a. 



Does anyone know to remove it?
That's DND (Do Not Disturb)


  DND is  a feature which after enabling you aren’t disturbed by
  notifications or other forms of incoming communication. Do Not
  Disturb(DND) can be set automatically or manually based on a few
  parameters that you control.




One way to disable DND is to  drag down your Notification Panel and select DND from the different toggles.

Alternatively navigate to Settings >> Do Not Disturb and disable it.

Acknowledgements

DND (Do Not Disturb) - A Nice Way To Block Unwanted Notifications!!