Hey, I was doing my first python project(and that is a billing system) and I was using this YouTuber called "Coding Lifestyle 4u" as my guide. He built this "search" button to search a bill by using the bill number and I have attached the functionality code for that button. The thing is it ain't working. I have did exactly what he did, even connecting the command to the "billnumberentry" but the error message keeps popping again and again. I'm losing my mind. Can someone tell me what to do?