Phone requiring bootup pin, HELP! ASAP!

A

AC Question

_Phone_
ZTE ZMAX PRO Android 6.x

I loaned my phone to a relative for a couple hours. I took off all security (fingerprint, and backup PIN). Upon receiving phone back, I restored my fingerprints and backup swipe pattern.

In my pocket, the phone power button was held down and rebooted. Now it is asking for a reboot pin number. The problem is.. I don't have a pin number! I did set the phone to have reboot security, always have. But now I don't have a pin to boot it up.

Can anyone please help. It is now saying that I only have a few tries left and it will wipe everything out.

Please help me ASAP!
ps.. this is my phone, I can prove it in many ways.