The lack of synchronization occurs because of checked-out projects. Integration Hub transfers data only from those projects which are checked in Project Online. If a project is checked out to some user in Project Online, Integration Hub will be unable to record any data to this project until it is checked in. Therefore, a data transfer will be postponed, and task updates will be recorded again every 5 minutes. If there is a data transfer consisting of 10 projects and only one checked out project, an entire data transfer will be postponed every 5 minutes. Having postponed jobs in Integration Hub may lead to data inconsistency and/or losing some updates in Project Online/Jira. It is highly recommended to check a project in and publish it in Project Online once all necessary updates are made in the project.