Question on Tkinter if anyone has any experience with it

After going through some of the python course, I have started on my own project. It’s an expense tracker. I’ve set it up so you can use the Tkinter to interact with a pop up window which allows, you to add expenses and income for a certain date, remove expenses for a date, month, or year, and view results of data the date, the month, the year, or a specific category. I am done with most of it, but stumped on why Tkinter is generating dead white space on the bottom, when I have set the whole background to black. If you need to look at my code its GitHub - soham767patel/ExpenseTracker. Window.py and DataCollectio.py are the two main files, main.py was my prototype using command prompt.