I am working on two functions in Azure Functions

`Timer Function` and `Http Trigger Function`

My timer functions runs every 1 hour and it executes the http function via an Http Client.

Now I do get an error **Synchronous operations are disallowed**

And I know how to solve this using the [article](https://stackoverflow.com/questions/59379971/enable-synchronous-io-in-azure-function) on stack overflow 

But I am curious as why am I getting this error?

Whats the cause of it?

The error doesn't occur when using Postman.

My Timer Code

```
Azure Functions Core Tools (3.0.2245 Commit hash: 1d094e2f3ef79b9a478a1621ea7ec3f93ac1910d)
Function Runtime Version: 3.0.13139.0

 Host configuration file read:
{
   "version": "2.0"
}

```

```
public static class DoSomeStuffTimer
    {
        [FunctionName("DoSomeStuffTimer")]
        public static void Run([TimerTrigger("0 0 7 * * *")]TimerInfo myTimer, ILogger log)
        {
            try
            {
                log.LogInformation($"C# DoSomeStuffTimer executing at: {DateTime.Now}");
                string url = Environment.GetEnvironmentVariable(EnvironmentKey.HostKey) + "/api/DoSomeStuff";
                HttpClient client = new HttpClient();
                client.PostAsJsonAsync(url, new DoSomeStuffRequest());
                log.LogInformation($"C# DoSomeStuffTimer executed at: {DateTime.Now}");
            }
            catch (Exception e)
            {
                log.LogInformation(e.ToString());
            }
        }
    }

```

My Http Code

```
public class DoSomeStuffFunction
    {
        [FunctionName("DoSomeStuffFunction")]
        public async Task<IActionResult> Run(
            [HttpTrigger(AuthorizationLevel.Function, "post", Route = "DoSomeStuff")]
            HttpRequestMessage req,
            ILogger log)
        {
            var response = new ContentResult {ContentType = "application/json", StatusCode = 200};

            try
            {
                DoSomeStuffRequest
                    request = req.Content.ReadAsAsync<DoSomeStuffRequest>().Result;
    }
catch (Exception e)
            {
                log.LogInformation(e.ToString());
            }
}
}

```