Instead of getting a DUNS number through the dnb.co.in website, you can get Apple to make this request for you. Simply submit the form to "look up" your DUNS number on Look up your D-U-N-S Number even if you don't have it. If the website is unable to find it, it will allow you to submit the form to acquire it.
A few days after submitting this form, I got an email from dnb.com, which warned me that I don't have a company, and therefore can't get a DUNS number:
Case # 2489474 has been resolved.
Tracking Id: REDACTED
Case Number: REDACTED
Resolution Date/Time: December 20, 2021, 05:55 PM (UTC)
Business name: ORGANISATION NAME
Duns:
Location: London Greater London GB
Requester's Own Request Key: REDACTED
Concern category: Add business - Mini Inquiry - Identity Data Only
Resolution: D-U-N-S Number already exists
Sub-Resolution: Verified through national registry
Resolution comment: Please note a search of our database revealed
no listing for ORGANISATION NAME at the address provided. Attempts
to contact the business was unsuccessful to verify the business.
Please note based on the request returning the best partial name
match. Delivered DUNS for ORGANISATION NAME is REDACTED.
Updated Information:
Resolution Duns: REDACTED
Business Name: ORGANISATION NAME
Address
REDACTED, BUT INCORRECT ADDRESS
Your milleage may vary, as I did this in the UK.
Unfortunately, this email from dnb confirmed that I need to be a registered company to get a DUNS number and create an Organization account.