Data Variable Create Record setup

I’ve got my own REST API running and using Postman I’m able to create a record like this:

I am having trouble configuring this in AppGyver:

image

I get this error:

The code I have in the API is this:

router.post("/:id/messages", (req, res) => {
const { id } = req.params;
const msg = req.body;

if (!msg.lesson_id) {
    msg["lesson_id"] = parseInt(id, 10);
}

Lessons.findById(id)
.then(lesson => {
    if (!lesson) {
        res.status(404).json({ message: "Invalid Id" });
    } 
    // check for required fields
    if (!msg.sender || !msg.text) {
        res.status(400).json({ message: "Must provide sender and text" });
    }

    Lessons.addMessage(msg, id)
    .then(message => {
        if (message) {
            res.status(200).json(message);
        }
    })
    .catch(err => {
        res.status(500).json({ message: "Failed to add message" });
    })
})
.catch(error => {
    res.status(500).json({ message: "Error finding lesson" });
})

});

Any ideas what I am doing wrong?

I’ve found the issue I think!
I needed to create the URL place holder