@Jaiswal, Nitin - Admin Welcome to Microsoft Q&A Forum, Thank you for posting your query here!
Please follow the below action plan and check if that helps:
Plan 1:
Could you please check if you have enabled the All networks
access under the Networking setting within your Azure OpenAI resource as shown below ?
Plan 2:
Ensure that there are no Private endpoints configured:
Plan 3:
Could you please confirm if you have a proxy / firewall within your corporate network ? If Yes, Please check if you can bypass it and then try testing again.
Hope this helps. If you have any follow-up questions, please let me know. I would be happy to help.