If you are not using regulator 1, connect PVIN1, DVDD1, LX1, PGND1, and EN1 to GND. Also, connect FB1 to COMP1.
If you are not using regulator 2, connect PVIN2, DVDD2, LX2, PGND2, and EN2 to GND. Also, connect FB2 to COMP2.
If you are not using regulator 2, connect PVIN2, DVDD2, LX2, PGND2, and EN2 to GND. Also, connect FB2 to COMP2.