How can I connect from C# to EC2?

Question

please help if you can! I am running a C# windows service on PC, and want to connect from the program to my EC2 server instance on AWS. The program keeps telling me it cannot connect via SSH. If I try to connect via command prompt, I can login with my PEM key and credentials. Error that I receive is:

Error connecting to EC2: Renci.SshNet.Common.SshException: openssh key type: ssh-rsa is not supported.

Here is my code snippet, I hope someone can help:

            // Specify the EC2 instance details
            string serverAddress = "ec2-13-244-98-241.af-south-1.compute.amazonaws.com";
            string username = "henk";
            string privateKeyPath = "E:\\Inovo\\CapitecEC2Uploader\\henk.pem";

            // Establish the SSH connection
            try
            {
                Log.Debug("try connecting to EC2: " );
                var privateKey = new PrivateKeyFile(privateKeyPath);
                var connectionInfo = new ConnectionInfo(serverAddress, username, new PrivateKeyAuthenticationMethod(username, privateKey));
                using (var client = new SshClient(connectionInfo))
                {
                    client.Connect();
                    Log.Debug("connected to EC2: ");
                    client.Disconnect();
                }
            }
            catch (Exception ex)
            {
                Log.Debug("Error connecting to EC2: " + ex.ToString());
            }

I tried to convert the key to *.PPK also, with no success.