If your TMP application's declined, a comment would generally be added by the Corridor Access Manager or Traffic Management Coordinator to let you know the reasons why it was declined. The comment would be displayed in the History panel of the TMP, and an email notification would be sent to you as well. A revision will need to be created before changes are made. 

To revise a TMP and make changes to it, you can click on the 'Create revision' link on the TMP, under the Layouts section.