Receiving 405 errors when trying to POST JSON information into webapi

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C#

ASP.NET

JSON

WebAPI

I've been trying to send POST messages where the message was from an appsettings.json file that I converted into a string.

What I have tried:

Program.cs

static async Task SendPost(string jsonMessage)
        {
            string url = "https://localhost:44312/GeneratorStatus";
            HttpClient client = new HttpClient();

            var response = await client.PostAsync(url, new 
            StringContent(jsonMessage, 
            Encoding.UTF8, "application/json"));

            Console.WriteLine(response);
        }

jsonMessage in this case is just a string that reads:

TestLaptop has encountered an error at 09.28.2020 09:15 AM/email1@gmail.com/email2@gmail.com/email3@gmail.com

This is my controller:
GeneratorStatusController.cs

[ApiController]
    [Route("[controller]")]
    public class GeneratorStatusController : ControllerBase
    {
        Emails emailList = new Emails();

        static List<string> strings = new List<string>()
        {
            "value0", "value1", "value2"
        };

        [HttpGet]
        public List<string> Get()
        {
            return strings;
        }

        [HttpPost("{input}")]
        public List<string> Post(string input)
        {
            strings.Add(input);
            return strings;
        }
    }

When running my program.cs while having IIS express hosting my server, I keep receiving a 405 error when running program.cs. This is the full "response" variable:

StatusCode: 405, ReasonPhrase: 'Method Not Allowed', Version: 1.1, Content: System.Net.Http.HttpConnectionResponseContent, Headers:
{
  Transfer-Encoding: chunked
  Server: Microsoft-IIS/10.0
  X-Powered-By: ASP.NET
  Date: Mon, 28 Sep 2020 13:18:49 GMT
  Allow: GET
}
[09:18:49 INF] Ending service