I've got the same as blue.

Received some messages, to which i replied, but all my messages to them disappeared, and then i quit and restarted wazapp (via menu) and i noticed it takes a much longer time to load conversation with my buggy contact.

I remember someone saying that potentially database was full, but I have no idea how to check if that's what's going on here. The wiki suggest a complete reinstall of wazapp, but i'm not sure if "not receiving messages" is the same as me receiving them from all contacts but for one of them, they then disappear.

It's now even more confusing for me, because after opening the database and having a geese at it, everything is in there, properly, and i can read all of the messages perfectly.

Even more details, log output:
file:///opt/waxmppplugin/bin/wazapp/UI/Conversations/js/conversations.js:74: TypeError: Result of expression 'message.media' [undefined] is not an object.

definitely confused now, appreciate any/all help!