How do i get into a 4g lte that has been reset but wants synced account that was on it before.

I just got phone from someone who left their Gmail account on the phone. Had a pattern lock on it and my little one tried it to many times to where it reset and now I don't know or have access to get previous synced account. What do I do???? Help?

The phone will remain permanently unusable unless and until those details are entered. It's a security feature. Contact the account holder.