HELP! One Drone Flyaway during RTL and 2nd drone Fly away during Takeoff

I have never experienced any flyaway from last 2 years but suddenly I have experience 2 flyaway which leads to the loss of my 2 drones. I am not able to understand what happened? (1019.6 KB)

In 1st drone (FLYAWAY DURING RTL)it was showing compass variance and in 2nd (FLYAWAY DURING TAKEOFF) it shows GPS Glitch.
Please guide me to solve this as i am not able to detect the exact reason of flyaway. I have attached logs. I am in no conditioned to fly my last drone Financially as well as technically.

Is Anybody there who can help me ?