Nodes sometimes don’t see each other. Why?

Noticing that sometimes my Heltec v3 nodes will not auto-discover each other. Pretty close to defaults for settings, Freq. set to default zero, was running Primary Channel without naming, fixed that but had no effect. Curious about the steps in the auto-discovery process and generally about neighbor relationship negotiation. Is there a Wireshark type packet capture tool with protocol decodes for Lora?