Strange, I'm on Version: v0.1.0 (5ad4dfa) and doesn't work
Discussion
His profile doesn't even have a lightning icon

Now I see sorry. And I was able to zap. Thanks.
This issue might be that his metadata you retrieved yesterday was an older version without the Lightning address. Jumble caches data for a day, hahaha
Maybe lightning address shouldn't be cached, because it's an important data?
It is stored in the kind 0 event along with the avatar and username. Caching it for a day shouldn't have too much of an impact.
We can test it for a while to see if it's necessary to query the latest lightning address before zapping