Why did my BLU R1 HD suddenly came to the Android Recovery System menu?

[AC Question]

A few days ago my phone started acting slow, today while I was using it the system rebooted and the Android Recovery System menu came on, I tried to follow all the options, but I haven't been able to get my phone back to normal. When I click the option "Reboot system now" my phone will go off and go back to the same recovery system menu. I don't know what else to do, I would appreciate your help, thanks.