Anyone know how to fix this?

Ok I went to bed left my phone on charger. Got up turned it on and get this screen that says if I want to download new OS push volume up to continue or volume down to cancel this. I never asked it to do anything of this type period! It refuses to recognize me pushing the volume key down to get out of it and cancel. I have tried factory reset several times no good. I can only boot to safe mode when I try to reboot it goes back to that screen every single time. PLEASE somebody HELP!!!