SendSmsWhenDelivered.cs

public class SendSmsWhenDelivered
{
    private readonly GetShipmentContact _getShipmentContact;
    private readonly SmsOptions _options;

    public SendSmsWhenDelivered(IOptions<SmsOptions> options, GetShipmentContact getShipmentContact)
    {
        _getShipmentContact = getShipmentContact;
        _options = options.Value;
    }
    
    public async Task Handle(Delivered delivered)
    {
        var contact = await _getShipmentContact(delivered.ReferenceNumber);
        
        await MessageResource.CreateAsync(
            body: $"{delivered.ReferenceNumber} Package Delivered!",
            from: new PhoneNumber(_options.From),
            to: new PhoneNumber(contact.PhoneNumber)
        );
    }
}