I think it's because this email address does not conform to the standards in https://en.wikipedia.org/wiki/Email_address
The domain name part of an email address has to conform to strict guidelines: it must match the requirements for a hostname, a list of dot-separated DNS labels, each label being limited to a length of 63 characters and consisting of::§2
- uppercase and lowercase Latin letters
9, provided that top-level domain names are not all-numeric;
-, provided that it is not the first or last character.
In your case, the domain is all-numeric, which likely is the reason that these addresses are invalidated.
Hi Atlassian Community, My name is Avni Barman and I am a Product Manager on the Atlassian Access team! One of my top priorities is to help make the administrator's life easier through improved pro...
Connect with like-minded Atlassian users at free events near you!Find an event
Connect with like-minded Atlassian users at free events near you!
Unfortunately there are no Community Events near you at the moment.Host an event
You're one step closer to meeting fellow Atlassian users at your local event. Learn more about Community Events