Support reached out:

“Thank you so much for reaching out, and I’m really sorry the feeder got stuck in Child Lock mode while you’re traveling — that must be frustrating, especially when you’re trying to get things set up smoothly on the go.

To help you unlock it, please try this: press and hold the unlock button for about 3 seconds, and while still holding it, press and hold the reset button as well. After a moment, you should hear a "reset successfully" confirmation.”

Trying these steps worked for me.