You’re telling Thunkable: “Get info from a server (API). Add a variable’s value to a list.” Thunkable is going to begin the API call and then immediately add the “empty list” value of that variable to the list. An API call can take several seconds to complete. So to insure that you are adding the correct value to the list, you need to – as @muneer suggested – move that “in list” block inside the “then do” section which only runs after the API call is processed.