C# 未找到API网关Websocket@连接终结点

我正试图从$connect路由向可能连接的客户端发送套接字消息。我成功地从dynamodb检索到连接id。每当我尝试发送任何内容时，都会出现以下错误：

No method found matching route %40connections/aM50DdTXCYcCGEA%3D for http method POST

我用来发送的代码：

Amazon.Runtime.AWSCredentials cd = new Amazon.Runtime.BasicAWSCredentials("*******", "******");

var domainName = request.RequestContext.DomainName;
var endpoint = $"https://{domainName}/{stage}";
context.Logger.LogLine($"API Gateway management endpoint: {endpoint}");

 apiClient = new AmazonApiGatewayManagementApiClient(cd,
                new AmazonApiGatewayManagementApiConfig
                {
                    ServiceURL = endpoint,
                    RegionEndpoint = Amazon.RegionEndpoint.USEast2
                });
Message testMessage = new Message()
            {
                AppId = "TestApp",
                CommandData = "Testing"
            };


MemoryStream stream = new MemoryStream(Encoding.UTF8.GetBytes(JsonConvert.SerializeObject(testMessage)));

PostToConnectionResponse response = await apiClient.PostToConnectionAsync(new PostToConnectionRequest()
                    {
                        ConnectionId = Uri.EscapeUriString(existing.ConnectionId),
                        Data = stream
                    });

我似乎找不到任何东西可以说明POST的端点为什么不工作（我在nodejs中有一个工作示例，但我们需要在.Net中完成）。如果有人对我如何找到问题所在有任何建议，我将不胜感激

我已经确认端点与部署的WebSocket API网关url匹配

Visual Studio 2017

.Net核心2.1

AWSSDK.API网关管理API 3.3.100.23

---

谢谢

我用相同的代码做了更多更少的工作，而且效果很好

        AmazonApiGatewayManagementApiClient client = new AmazonApiGatewayManagementApiClient(new AmazonApiGatewayManagementApiConfig() {
            ServiceURL = "https://" + request.RequestContext.DomainName + "/" + request.RequestContext.Stage
        });

        MemoryStream stream = new MemoryStream(Encoding.UTF8.GetBytes(JsonConvert.SerializeObject(document)));
        PostToConnectionRequest postRequest = new PostToConnectionRequest()
        {
            ConnectionId = request.RequestContext.ConnectionId,
            Data = stream
        };

        var result = client.PostToConnectionAsync(postRequest);
        result.Wait();

---

我最终删除了所有IAM角色并重新创建了它们。我猜有些东西配置错误，或者如果IAM使用任何类型的缓存系统，可能会锁定到旧版本。不过它现在起作用了。很抱歉延迟在这里发布我的发现

你的答案只提供了代码以外的信息。详细说明为什么要做事情