The configuration of the DUTY bits (DUTY[2:0] in CTRLA) define the number of COM lines used and thus the number of phases. BIAS bits (BIAS[1:0] in CTRLA) define the number of bias voltages. SAM L22 SLCD supports up to eight COM and up to three bias voltages.
For this application, Segment LCD1 Xplained Pro requires four common terminals and segment terminal 0 to 23 to control all segments. So, the Duty and Bias bits are configured as 011 and 10 respectively.