Unfortunately, two-letter domain names (such as ab.com) are not available to be registered.
In the older gTLDs such as .com, .org, and .net, all possible 676 variations have been already registered, and in the newer gTLDs, two-letter domain names are not allowed.
Article ID: 160
Created On: Thu, Mar 5, 2015 at 4:30 PM
Last Updated On: Thu, Apr 23, 2015 at 12:07 PM
Online URL: https://www.heartinternet.uk/support/article/why-can-t-i-register-a-two-letter-domain-name-with-you.html