It turns out my SPI communication was off. It’s working now, and thanks for the quick reply!!
You can write to the control register and set the RANGE bit to 0 to select the range from zero to 2xVref. May I know what is the voltage value of the VDD supply pin? The VDD supply pin should be 4.75V to 5.25V.
I can't seem to get the range bit to properly select the 2*vRef range when working with this part. The SPI comms work well and I have check them. Has anyone seen this before?