Help: 1 frame video from Expression Editor

Hi, I have the following workflow. However, it's creating a video of 1 frame. I followed tutorials & can't spot the different in my workflow from other workflows. Sorry for such a newb question. Just want to get it working. <img width="3819" height="1919" alt="Image" src="https://github.com/user-attachments/assets/16ce0806-3195-41e1-894b-30f4b3b413c3" />