SOLVED!
So I have placed a cap between rst and gnd, to be able to enter the serial monitor without triggering the reset that would restart and correct the issue. I have noticed that the correction value is calculated way too high. that was a direct pointer that at the moment of the calculation one sensor is way off. I have added a delay between the sensor reading and the calculation of the correction, and that solved it. I have accurate measurements and functionality on all power sources with power cycling of different intervals.