ORP sensor value is not stable

Hello, 

 

I purchased ORP sensor Gravity: Arduino Analog ORP Meter - DFRobot
and testing.

 

I'm having an issue with my DFROBOT ORP sensor, and I hope someone can help me figure out what's going on. I've connected the sensor to my ESP32 Firebeetle ESP32E  and I'm getting random mV readings that don't seem to correspond to the actual water quality.

 

Issue Description:

The problem I'm facing is that the mV values I'm getting from the sensor are fluctuating wildly, even in a stable water environment.
The sensor should ideally provide a stable ORP reading, but I'm not getting the expected results.

 

The sample code is from product wiki Analog_ORP_Meter_SKU_SEN0165_-DFRobot

 

The getting value is as attached file

 

Regards,

San