Throw-in liquid level transmitter issues

I recently received 2 Throw-in liquid level transmitters from Little Bird. I went to the relevant site and used the DFROBOT installation details to install. 

I am experiencing several problems. Firstly, I don't think there is an issue with product failure, because as I said I have two of these and I have swapped in and out all components including the sensor, the voltage converter, and the Arduino units. The same results have been obtained. I am using a Powertech DC Regulated power supply unit to provide 13.84 V. I am receiving readings in mm that are 200mm out. I used the code from the DFROBOT datasheet: https://www.dfrobot.com/product‐1864.html?search=KIT0139/7‐12‐19

In this code I have changed the water density reading to 1.2 which seemed to calibrate a better reading. However, when I remove water from the clear container the reading stays the same. There is no level change being indicated. Further, when I remove power supply to the sensor, the sensor still measured the same reading continually. I am following the circuit diagram correctly with the positive lead coming from the 13.84 regulated power supply and going into the positive input of the current to voltage converter. The positive lead from the sensor going into the negative supply of the Current and Voltage converter. And the Negative lead from the sensor going into the ground of the power supply.

Please assist.