Deleted tasks are then grouped together in a section. To access it :
From your personal space or a specific workspace, click on the dropdown menu on the right of the screen and then on Deleted Tasks
The deleted task is shown here
Restore deleted tasks
This feature allows you to cancel the delete task action, making it reintegrate the current tasks.
Click on the task to restore
Click Restore on the action bar or, from the details pane, click the button with the three vertical dots and then click Delete
Info: It is also possible to restore several tasks at once by selecting them and clicking Restore.