Hi sudesh,
The error is generally a transient control plane hiccup or a browser session state getting out of sync. You can try forcing a hard refresh of your Free edition workspace UI or completely close and reopen the notebook to trigger a fresh session request.
If the issue persists after a hard refresh, it points to a temporary serverless capacity constraint in your workspace's specific cloud region. Since Databricks serverless compute provisions resources dynamically behind the scenes, you can occasionally hit these limits during peak hours when the regional pool is heavily utilized. Give it a few minutes before trying again.
