Problems with Magic mouse out of nothing. Discovery mode undetectable?

I got troubles with my Magic Mouse using it on Macbook air 13''.

The problem came unexpected. The mouse was not responding at all, so i decided to turn it off. There was no effect after i tried again. So i got the mouse unpaired but now it seems that I cant see it in the Mouse settings, or in the Bluetooth devices no mater that the Mouse is on discovery mode after I turn it on.

What should i do to get it back working.

10x!

P.s. The mouse is turning off the light indicator after several minutes in Discovery mode while the Macbook air is still looking for it.