Welcome to Android Central! They stole it, reset the phone, and then you were able to recover it? That's lucky. It's also odd that they were able to reset the phone, since it should have Google's Factory Reset Protection, which requires the user to enter the Google account and password in order to complete the factory reset process. But since you mention that you're trying to enter your email and password, then perhaps you got it back after an unsuccessful attempt to reset it.
You could try connecting a basic USB keyboard via an OTG cable.