Help with app to receive messages over Bluetooth and log times received in a CSV file

I have an assignment where I've created a device that sends a message over Bluetooth when it senses motion, and I now need to create an app (in App Inventor) that will receive the message and save the time it was received to a CSV file.

Any help at all would be appreciated! Images of where I am so far are below.

Here is a logger to TinyDB ...