RachelRachel 133k6767 gold badges315315 silver badges510510 bronze badges two three Rachel, that you are a gorgeous genius!!! And that i am an idiot. Thanks a lot of for the answer. I was binding to self and didn't have a 'ConfigurationModel' property in my IncrementingTextBox class. So your DataContext for "video_length_textbox" https://m3mgolfhillssector79.blogspot.com/2025/06/jms-mega-city-sohna-redefining.html