Hi @NNG Admin,
Sorry for the delayed response,
If your quota usage is currently 0, it may indeed be the reason you are unable to deploy the GPT model in the Southeast Asia region. Quota is assigned to your subscription on a per-region basis, and you need to have an available quota to create deployments. If you have not been allocated any quota for that region, you will not be able to proceed with the deployment.
To resolve this, you may need to request a quota increase for the Southeast Asia region. You can submit a request for a quota increase through the appropriate channels provided by Azure.
here is the link Request more quota.
here is my quota,
I hope you understand.
Thank you!