Team discovery let's people from your organization see your team and requests to join. Generally, people using the same email domain should be able to discover your team and request to join.
By any chance, if you are migrating your company's email address from one domain to another (ex: from example.com to example.co.in), the new domain won't automatically be updated under team discovery at the moment.
But, don't you worry as this can be fixed by disabling and re-enabling the Team discovery option under the settings page
Note: As your email address has been updated, you might be prompted to verify your email address during this process