Hello, Hero Candidates!

We're sorry to hear about your upsetting situation!


To solve this problem, we would like to ask you to use the method below.


1) Check if another device is linked to the account(including a PC Android emulator).

2) Please check the network(Wi-Fi / LTE) connection status.

3) Please reboot your device or restart the Devil Book app.

4) Free up 2GB or more of free space on your device, reboot, and run the Devil Book app again.

5) Please reinstall the Devil Book App.

   ※ If you use this method before your account has linked, your account will be gone. 

        So please link the account with Google or Apple, or check the ID and code.

   ※ To confirm your account Link information's ID and Code, please refer to the route below.

       Route : Ingame main screen - menu icon - option (Cog Icon) - Link Information


If this problem persists, please email us with your information to devilbook@ngelgames.freshdesk.com 


1. Situation 

 - Time : ex) 21-01-31 15:44 [PDT]

 - Please briefly write about the problem.

2.Ingame Information

 - Account name : ex) ABC#12DE3

 - Game Version : ex)  

 - Time : ex) Feb 12, 11:14:45 [PST]

3.Device information 

 - Devico Name : ex) Galaxy Note 8+

 - Device OS : ex) AOS 5.1.1

 - Device Language : ex) English


※ If you attach screenshots or videos of your problem, we can help you furthermore.