Please note that the application cannot be stored in the external Memory.
Therefore, even if it seems there are enough space in the device,
The installation might stop.
Please follow the step below and re download the game to reslove the issue.
■ Delete the Internet Cache and Application.
* Application: Delete unnecessary Caches in Setting > Apple
* Internet: Run internet > Click Menu bar at the top left > Settings > Privacy > Delete Personal Data > Delete Cache
■ Delete unnecessary Apps and information
* Please sort out and delete the unnecessary Apps, Photos, and Video clips stored in the internal storage.
※ Steps may vary per device.