I run Confluence for my company, our domain is NAME.atlassian.net - and I have just received a "request to join Confluence". Our emails are NAME.com.pl, and I received a request from a person whose email is NAMErs.com.br - is that person a hacker who bought a similar domain name to trick me and gain access, or is this some feature that matched him to our Confluence just because of a similar domain name?