I tested it with two nearby phones. All messages work via mesh, both for the sender and the receiver.
Always testing with 2 nearby phones, in geohash this time, if I decide to send a private message or receive it from that person, the messages are all white without text and without even the time of receipt or sending.
So the problem is about sending and receiving messages privately using geohash, when from the list of people online, you choose either to send or receive the message, with blank messages and therefore no text.
I tested it with two Xiaomi phones, both with the pre-release of version 1.6.0-rc3