Yeah. I input the npub for the recipient and it gave me an error, but still creates the chat, just messages won't go through.
I've tried using my own nsec, creating a new one in app, both >10 times. Still no dice.
Last worked for me yesterday morning.
I've also attempted uninstalling and reinstalling both straight from apk on their site, and through zapstore, both multiple times with no change.
Might be putting this on the back burner until their next update.