TPD6S300: ESD cause CC pin drop issue

Hi,

Below figure is using TPD6S300 to protect USB port, when doing ESD discharge test(Air & Contact) to type-C connector or metal enclosure,

CC pin voltage level from 1.8V drop to 800mV, it caused PD controller consider CC pin disconnect and cut off PD charging, and re-connect after few seconds because CC pin back to 1.8V level.

Is it normal behavior? Or any suggestion can improve this voltage drop?

Customer reply only using TI TPD6S300 have this voltage drop, if using other brand protect IC(ex. UPI UT0300P, or Richtek RT1738), have no this voltage drop behavior.

CH1: CC1

CH2: VBUS

Thanks!

Jeff