LocalNotification in Xamarin Forms not always received

I’m developing a mobile app in Xamarin Forms. I have develop local notifications using the latest versione of https://github.com/thudugala/Plugin.LocalNotification

Many times notifications work great, but sometimes notifications are not received/sended or sometimes notifications are recevied all together in a wrong moment compared to the scheduled time.

Most of the tests were made on iOS on real devices. The code I use is more or less this:

var notification = new NotificationRequest
{
    NotificationId = idNotific,
    Title = "myApp",
    Description = txt,
    ReturningData = "myData",
    Schedule =
    {
        NotifyTime = timeToTake,
        RepeatType = NotificationRepeat.TimeInterval,
        NotifyRepeatInterval = new TimeSpan(intervalDays,0,0,0)
    }
};
LocalNotificationCenter.Current.Show(notification);

if (Device.RuntimePlatform == Device.iOS)
{
    var notificationNext = new NotificationRequest
    {
        NotificationId = idNotific,
        Title = "myApp",
        Description = txt,
        ReturningData = "myData",
        Schedule =
        {
            NotifyTime = timeToTake,                       
        }
    };
    LocalNotificationCenter.Current.Show(notificationNext);
}

For iOS, using TimeInterval, I had to add an extra schedule because otherwise the first notification is not sended. The “idNotific” is a big integer number, “timeToTake” is a DateTime and “intervalDays” is a small integer.

I'm trying to figure out why they sometimes don't work properly. I tried to understand if there is a something different from when notifications work and from then don't work, but apparently it's all the same.

Do you have any suggestions? Do you need more info?

Thanks Luca