When you have clicked on Paid, you will be asked if you wish to create a utilisation. Clicking OK brings up the utilisation screen. You can also bring up the screen directly from the transaction by clicking on Create Utilisation.

Enter the relevant details and click on Create Utilisation. 

Note: For the question "Do you wish to cancel the LC balance after this utilisation?" - if you select Yes, it will set the status of the LC to cancelled.