I have a custom function that generates the JSON, but when I assign the value in the action, it seems like it doesn't send the JSON. I get an error from the API saying that the JSON is not correct. In tests, it works, but when I assign the JSON in the action, it seems like it's not in the correct format. I'm not sure if I should return a string or a JSON in the function; I've tried both, and it doesn't work.