2nd hand nexus 5x had TWRP installed which is now blocking OTA to Android 7.1

[Android Central Question]

Bought a second hand Nexus 5x. I didnt realize the previous owner had installed TWRP.
He sold it as a factory unlocked phone.
On attempting to update to Android 7.1, when the phone rebooted im getting the resting android image and text "No Command". Nothing seems to get me passed this screen other than...

If I hold the power and vol down buttons, and go to Recovery Mode, I get the TWRP menu.

1. How do I get the phone to restart normally with no update.
2. Can I remove TWRP, if so how.
3. If I cant remove TWRP, how do I successfully update to newer android versions?

Thx!

 

[B. Diddy]

Moved to the Nexus 5X Rooting/Hacks forum for more specific traffic.