Hi @lakshmi,
Thank you for reaching out to Microsoft Q&A forum!
Based on the information provided, it seems like you are encountering an error while validating the identity for OpenAI on your data stored in Blob storage. To troubleshoot this issue, I would suggest verifying that you have assigned the correct RBAC roles. For more info, please refer to Role assignments. Also, I suggest using a different region and see whether it works.
I hope this helps! Thank you.