Hi Abhijit,
If your organization is using CASS or SERP for address cleansing in the US or Canada (respectively), you will have detailed info on the verification of the address and why it was partially successful or failed. However, even without these optional features/services, you can generally gather most of the details you're requesting by simply examining the values returned within the AVC code returned from Loqate. Specifically, the second and third characters in the AVC code may help you to understand why the verification status is not being returned as "Verified."
Please find further details on our doc portal at:
https://docs.reltio.com/datacleanse/understandavc.html