I have no experience with stm32CubeMX but it appears that join requests are sent, but the join accept is not received. Either because latter is not sent or because it is not received/recognized by the node.
This indicates that the event is triggered by the LoRaWAN stack but is not handled by your application code.
Do you have access to a nearby gateway and its traffic in the TTN console? Do you see any join accept downlink messages in respons to join requests?
Please don’t post screenshots of code. See: How do I format my forum post? [HowTo]