PLZ HELP!! Nexus 6p keeps booting into TWRP menu

Today and after deciding to simply restart my Nexus 6P, it booted into TWRP menu, I tried to reboot again, but no luck. can someone please help? :(

Note: The root used to simply work fine for about a month now.

from xda-developers http://ift.tt/288zMOT
via IFTTT