In the final episode of the kenobi television series we see
Qui-Gon Jinn appear before kenobi as a force ghost.
However, if I remember correctly in the Clone Wars television series it was established that
Qui-Gon did not complete his training, and so could only appear to the living voice-only. In fact Yoda had a lot of trouble trying to listen to him, and could only properly communicate with him once he landed on a planet that was strong with the force (midi-chlorians?). Yoda then completed the trials that would allow him to properly manifest as a force ghost postmortem.
Did I miss something between these events?