My keyboard fails to connect

My blackwidow fails to connect to the computer. It tries to connect but fails every time(I don't know what to do) I tried restarting my pc but it didn't work, I have got this keyboard 21days ago and it is the first time when this happens. I have windows 10 and I hear in every 30ish seconds the unplugging sound. If I press shift+s il will wot show a capital letter (caps lock off)