When making a connection to JIRA, you may sometimes encounter a 404 error. To fix this, you need to make sure that your host name and username are properly given.
The hostname is your company's JIRA domain, and is typically in the form of <companyname>.atlassian.net (e.g. workato.atlassian.net)
Typically, your account name should be the first part of your company email address (part before the "@"). So if your email is firstname.lastname@example.org, your Username will be johndoe. For admin's the default username should be "admin"