So, what needs to be improved is the prototype. Also, try testing all the existing features for those who want to try Usability Testing. Because I also don't know which one the user will interact with, I can't force the user to do testing through the flow. That I create lets the user naturally use the prototype. From the prototype that I made, there are many paths that the user can take to achieve the goals of a testing scenario. You can see the user heatmap on how the result failed so that it is clear what the user interacts with, and I can also quickly inspect what needs improvement from our application prototype.