failed to detect gps location in pokemon game when applying fly gps

I recently install fly gps app and use the app in playing pokemon game with my zenfone3(z012D) and my zen pad (3s), both devices show error code "failed to detect gps location (12)", I follows every steps accordingly in settings up the app . I have no problem using the app with my oppo r9s plus phone,
please help me to resolve the problem mentions
thank n regard.
from Andy.