Debut does not have a way to disable update prompts. You may want to make sure that the license is registered.
To register:
1- Open Ddebut.
2- From the top left corner, click the "File" menu.
3- From the dropdown menu select "Register software..."
4- Enter your registration code (numbers-letters) and click on Register.
5-If successful, you'll see the "Licensed Software" status at the very top of the window, next to the program's name.
If it will have the same issue, you may want to do a clean install for Debut.
Thank you.