ESP32 and P-MOSFET controlled voltage divider
To &quot;turn off&quot; a PMOS transistor you must bring its gate voltage up to its source voltage. The source voltage for your transistor is the battery voltage, 6.6 V. Since your GPIO pin will only provide 3.3 V it will not be able to turn the PMOS transistor off.
You would probably be better off using an NMOS transistor between R6 and ground.