Based on the context provided, here are some potential causes and solutions:

1. Metadata Server URL: Ensure that the URL http://169.254.169.254/computeMetadata/v1/instance/service-accounts/default/token is accessible from your environment. This URL is used to fetch the access token for the default service account.

2. Service Account Permissions: Verify that the service account associated with your Databricks cluster has the necessary permissions to access the required resources. The service account should have roles such as Storage Blob Data Contributor assigned at the appropriate level (e.g., storage account level).

3. Service Account Configuration: Check if the service account being used is correctly configured and has not been deleted or recreated without updating the corresponding credentials in Databricks. If the service account was recreated, you might need to refresh or update the storage credentials.