You can contact firstname.lastname@example.org - (if you did not setup a password)-
You can goto recovery link https://lootgames.co/l/sprint/playkids/pages/recovery.html
or try restarting and following the steps.
if you did not see the above image ( try clearing storage cache/memory and restarting )
open app, click login , enter email
you might also try below on some phones - click i have an account
then click on playphone button to login
enter the sign up email