OFFLINE

a. If you started the game with Facebook account, please cancel auto login and tap the Facebook button to access your previous account;

b. If you started the game with quick register, you can see your previous account from the dropdown list in username section

If that doesn't help, please tell us

your username,

character name(s) (send us screenshot of your character),

server(s)

when did you log in for the last time,
when did you start to play the game,
which country and city are you in,

which timezone.

Which device did you use when you start to play the game? We need the specific product info.

If you make any purchase, please tell us your transaction ID, which can be found in the email you receive after the purchase.  And send us a screenshot of the confirmation email you receive.
Thank you