If a scheduled import was defined, you will need to a Windows Scheduled Task on the Web server hosting Issuetrak for the import to execute at the proper interval. If multiple scheduled imports were defined, account for the variation between schedules when creating this Task. Please see KB Article #1444 in our Support Site for instructions on creating this task.
Additionally, the Application URL must be accurate for the imports to process correctly. To verify this, navigate to Administration > System > System Settings > System Defaults and make sure the Application URL field accurate reflects your site URL.