In addition to the contacts interface, you can also add and assign companies. A company can then be set up with one or more domains, so that Sirportly can recognise and assign incoming tickets correctly based on the contact's email address.
To start, navigate to your contacts tab, and select View Companies on the right hand side:
Select a company name to view it in further detail, or select the number of contacts or tickets to view those that belong to the company.
To create a new company and assign a set of users, select New Company from the same companies page. By entering a domain for the email address, you'll be offered a list to existing contacts to then assign to the company.
This will in turn assign all tickets submitted by those contacts to the company as well.