unable to make a Compute Engine Instance in Asia-south1

I assume that you're receiving error The zone 'projects/XXX/zones/asia-south1-b' does not have enough resources available to fulfill the request. Try a different zone, or try again later.

I tried creating a VM in asia-south1 (a,b and c) on my account and was also unable. This situation is not caused by your quota, you can find explanation in documentation:

If you receive a resource error when requesting new resources, the zone you requested the resources in cannot currently accommodate your request. This error is due to the availability of Compute Engine resources in the zone, and is not due to your Compute Engine quota.

You can either wait for resources to be released, create machine in different region or make a Compute Engine reservation.