GoogleSignIn.getLastSignedInAccount returns null after GoogleSignIn.requestPermissions

I use

fun requestAdditionalPermission(activity: FragmentActivity) {
        if (!GoogleSignIn.hasPermissions(
                GoogleSignIn.getLastSignedInAccount(activity),
                Scope(DriveScopes.DRIVE_APPDATA))) {
            GoogleSignIn.requestPermissions(
                activity,
                REQUEST_APP_DATA_PERMISSION_REQUEST_CODE,
                GoogleSignIn.getLastSignedInAccount(activity),
                Scope(DriveScopes.DRIVE_APPDATA))
        }
    }

to request additional permission but after i restart the app GoogleSignIn.getLastSignedInAccount(context) returns null