I am using a Boron connected to Particle and Blynk clouds. My firmware uses SYSTEM_THREAD(ENABLED) and SYSTEM_MODE(MANUAL). I do not publish anything to particle. I occasionally see these error messages in the data console ( Tera Term) and I have no clue what it means, why it is happening or if it can be resolved. I should point out that even though I received this data, my Boron was still breathing cyan and responded to input from the Blynk app.
Thank you in advance
0041565095 [comm.protocol] ERROR: Event loop error 21
0041565096 [system] WARN: Communication loop error, closing cloud socket
0041565098 [system] WARN: Failed to load session data from persistent storage
Do you at any instance call Particle.connect()? (breathing cyan would suggest so)
Do you at any point call any function that may require a cloud connection (e.g. Particle.syncTime())?
What connection is Blynk using? (Particle cloud | TCP | UDP)
How do you do the UDP hole punching for the cellular connection? This would usually be done via the cloud task in the background every 23 minutes (default setting for Particle.keepAlive()) If your code is not actively talking to the internet at least once during the keep alive period, the system may be trying to do it for you by pinging the cloud server (even when not seeking a cloud connection).
For a more conclusive answer we'd need to see your code.