Getting System.IO.IOException: Failed to bind to address https://0.0.0.0:5001

I have a droplet on DigitalOcean, and my application works fine when I use HTTP. However, when I try to enable HTTPS for added security, I encounter the following error when trying to run the application:

System.IO.IOException: Failed to bind to address https://0.0.0.0:5001: address already in use.

I’ve confirmed that nothing else is using this port, and the address appears free when I check. The problem only arises when I attempt to install the application. I am using self-signed certificates, and I’ve ensured they are correctly placed and accessible. But I can't seem to get past this issue.

Below are the relevant parts of my configuration and code:

My appsettings.json

{"ConnectionStrings": {"DefaultConnection": "YOUR_DB_CONNECTION_STRING"  },"Logging": {"LogLevel": {"Default": "Debug","Microsoft": "Information","Microsoft.Hosting.Lifetime": "Information"    }  },"AllowedHosts": "*","Kestrel": {"Endpoints": {"Https": {"Url": "https://0.0.0.0:5001","Certificate": {"Path": "YOUR_CERT_PATH","KeyPath": "YOUR_CERT_KEY_PATH"        }      }    }  }}

program.cs

namespace HIDDEN{    public class Program    {        public static async Task Main(string[] args)        {            var host = CreateHostBuilder(args).Build();            await host.RunAsync();        }        public static IHostBuilder CreateHostBuilder(string[] args) =>            Host.CreateDefaultBuilder(args)                .ConfigureAppConfiguration((context, config) =>                {                    var builtConfig = config.Build();                    // Try to get connection string from configuration                    string configConnStr = builtConfig.GetConnectionString("DefaultConnection");                    // Fallback to environment variable if needed                    string envConnStr = Environment.GetEnvironmentVariable("DB_CONNECTION_STRING");                    string finalConnectionString;                    if (!string.IsNullOrEmpty(configConnStr) && !configConnStr.Contains("${"))                    {                        Console.WriteLine("Using connection string from configuration.");                        finalConnectionString = configConnStr;                    }                    else if (!string.IsNullOrEmpty(envConnStr))                    {                        Console.WriteLine("Using connection string from environment variable.");                        finalConnectionString = envConnStr;                    }                    else                    {                        Console.WriteLine("No valid connection string found.");                        finalConnectionString = "";                    }                    Console.WriteLine($"Final connection string: {finalConnectionString}");                    config.AddInMemoryCollection(new[] {                        new KeyValuePair<string, string>("ConnectionStrings:DefaultConnection", finalConnectionString)                    });                })                .ConfigureLogging(logging =>                {                    logging.ClearProviders();                    logging.AddConsole();                })                .ConfigureWebHostDefaults(webBuilder =>                {                    webBuilder                        .UseKestrel((context, options) =>                        {                            // Allow Kestrel to load endpoints from appsettings.json                            options.Configure(context.Configuration.GetSection("Kestrel"));                            // SSL configuration from .pfx file                            string certPath = "YOUR_CERT_PATH";                            string certPassword = "YOUR_CERT_PASSWORD"; // Password for the PFX file                            options.ListenAnyIP(5001, listenOptions =>                            {                                listenOptions.UseHttps(certPath, certPassword); // Use SSL for HTTPS                            });                        })                        .UseStartup<Startup>();                });    }}