Notifications for a device going online when it's turned off

lidor11

Hi, I've got TeamViewer installed on my pc and my smart android TV.

Every once in a while while on my pc, I get a notification that my TV has gone online while it's turned off..

How can I know if this is not a sercurity breach ?

I use the pc to control the TV with TeamViewer from time to time, so my worries is someone else might have access to it somehow