How do I send multiple recipient SMS using the Azure communication service SMS in c#

I am developing small web application to send SMS using Azure communication service for multiple recipients. I got a following code from official microsoft page and it is working for one recipient.

SmsClient smsClient = new SmsClient(connectionString);

        SmsSendResult sendResult = smsClient.Send(
            from: sms.From.ToString(),
            to: sms.To.ToString(),
            message: sms.Body,
            options: new SmsSendOptions(enableDeliveryReport: true) { }
        ) ; 

if I pass a list of recipients the "to" showing a syntax error.

SMS.cs

`public class SMS 
    {
         public SMS() { }

        public SMS(SMS sms)
        {
            if (sms == null)
                throw new ArgumentNullException(nameof(sms));

            From = sms.From;
            To = sms.To;
            Body = sms.Body;
        }

        [DataType(DataType.PhoneNumber)]
        public string From { get; set; }
       
        public string Body { get; set; }
       
        [DataType(DataType.PhoneNumber)]
        public string[] To { get; set; }
    }`

I modified the code like as below

 List<SmsSendResult> sendResult = (List<SmsSendResult>) smsClient.Send(
            from: sms.From,
            to: sms.To,
            message: sms.Body,
            options: new SmsSendOptions(enableDeliveryReport: true) { }
        ) ;

the error is

the ACS method parameter is

Can anyone please help in this?

You can refer to the sample example here on how to send sms 1:N list of recipients using azure communication service using Send or SendAsync function from the SmsClient with a list of recipient phone numbers.

Here is the sample example:

Response<IReadOnlyList<SmsSendResult>> response = smsClient.Send(
    from: "<from-phone-number>",
    to: new string[] { "<to-phone-number-1>", "<to-phone-number-2>" },
    message: "Weekly Promotion!",
    options: new SmsSendOptions(enableDeliveryReport: true) // OPTIONAL
    {
        Tag = "marketing", // custom tags
    });

IEnumerable<SmsSendResult> results = response.Value;
foreach (SmsSendResult result in results)
{
    Console.WriteLine($"Sms id: {result.MessageId}");
    Console.WriteLine($"Send Result Successful: {result.Successful}");
}

You need to Make these replacements in the above code:

• Replace <from-phone-number> with an SMS-enabled phone number that's associated with your Communication Services resource.
• Replace <to-phone-number-1> and <to-phone-number-2> with phone numbers that you'd like to send a message to.