MPQ8634BGLE high current

Hello, I am using the MPQ8634BGLE to create from 12V to 5V@18A.
unfortunately, the MPQ8634BGLE at 10A starts working bad.The output voltage is around 3.5V and the current is jumping between 7~10A. I tried to change the CBF RCS and RMODE to try different modes and also I changed the FB resistors for 1V output like the EVB.
attached schematics.

your help will be much appreciated