title: How to resolve the 4429 error in Azure TTS?
body: <p>I use Unity to develop my software and I have access to the Azure SDK, using code that is basically officially provided, it fails every few days and then every time I call it I get this error reported:</p>
  <p>Connection was closed by the remote host. Error code: 4429. Error details: The request is throttled because you have exceeded the concurrent request limit allowed for your sub USP state: 3. Received audio size: 0 bytes.</p>
  <p>What I know so far.</p>
  <ol>
  <li>If I delete the resource in Azure, recreate the new TTS resource, and change the secret key to the new resource's secret key, I can temporarily fix the problem</li>
  <li>The problem is not caused by me calling it too many times in a short period of time, I have tried calling it more times than the limit in a short period of time and this causes another error</li>
  <li>This problem does not resolve itself over time, I have tried not calling it all day and the next day the problem is still the same</li>
  </ol>
  <p>My current suspicions.</p>
  <ol>
  <li>could it be that I sent some kind of request or something, but didn't destroy it, and that caused the problem?</li>
  </ol>