Controller is not syncing

Hi there, yesterday my girlfriend decide she was gonna unplug my PS4 whilst I was on it so I couldn’t play! I tried to start it back up but now it just comes up with (connect DualShock with usb cable) witch I do but it does not works my controller just flashes and that’s about it I’ve tried with all 3 off my controls and it does not seem to work…. could someone help me please?