AW2721D, does it support DDC/CI?

I'm attempting to use DDC to control my monitor from the commandline but get either 

Failed to get current input for display 'Dell AW2721D(HDMI)': An operation failed because a DDC/CI message had an invalid value in its command field. (os error -1071241847)

or 

Failed to get current input for display 'Dell AW2721D(DisplayPort)': An error occurred while transmitting data to the device on the I2C bus. (os error -1071241854)
depending on if I use HDMI or displayport.  is it theoretically possible to do this ?  other dell monitors seem to have the ability to turn on DDC  is this something I can do ?