Weird crash with Hexacopter on Copter V4.0.7

Just recently I went out to fly my hexacopter July 12, 2021. The flight was about 3-5 mins away from completion, then the drone suddenly fell from the sky. The drone was still powered on when we found it. Batteries were reading about 81%, so I know the batteries didn’t die midflight. I reviewed the datalogs from the crash and could not piece together what had failed. The altitude graph does not show any decline upon it crashing, it simply stops recording data after ~13mins.
We suspected that our autopilot might have rebooted itself causing the drone to just suddenly fall out of the sky, but data was still being collected 20 mins later when we found the drone and finally powered it down.
I’ve attached the link to the datalog collected from the flight. The file was too large to attach to this topic. If someone could help me figure out what could have caused this crash, it would be greatly appreciated!!

[Datalog files ][(https://drive.google.com/drive/folders/1lYmQwEsvH_FL9EzkPHAOyC39AjBzTAhH?usp=sharing)]

Hi Joselinn,
Looks like you have a power issue:

The CubeBlack is rated to 5.7V:
https://docs.cubepilot.org/user-guides/autopilot/the-cube-module-overview

How are you powering the cube?

@IAMMATT good catch.
Also have a look at the current usage at the same time.
Looks like a power issue, maybe a short, and as mentioned, the cube won’t tolerate >5.7v
Do you have Zener diode protection on your inputs?

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I also thought that it could be a short. My question was if it was a short wouldn’t the cube be unable to work again. When tested the next day with the same hardware and not touching anything it was able to act like nothing happened.

It probably restarted when that happened, and that prevented it from be damaged. Check all of the cables and make sure the problem is solved before flying again

We hooked up the zener diodes as per requested, but they began to smoke shortly after the autopilot started up. We hooked them up to the power’s VCC 5V wires as well as ground.
The diodes being used were recommended on a few other forums (1N5338B 5W 5.1V zener diode), What could be causing the diodes to smoke?

Did you connect the Anode to GND and Catode to 5V?

Yes we did @amilcarlucas

Then your voltage is superior to 5.1 V

Yes, it averages 5.58 V. What would you recommend doing?

Reduce it at the source somehow. A zenner diode will have to burn a lot of energy in order to bring that down to 5.1 or 5.2