You will not able to find any issues if you see all blocks in the project as a whole. Divide it from the beginning and use “Do it” function in the companion.
So start from the beginning or start from the last point from where this error comes (in your case look for the dynamic cardview block)
In your case whenever you clicked that dynamic cardview, it doesn’t work like you wanted. so first check if the list you are loading is empty or have some items. I saw an error in the video you provided and according to that there is no such screen name as catwalls in your app.