MP6602 Stall detection

Hello,
I’m driving a stepper motor with MP6602 demo board. The motor is 24V 0.7 A, for peristaltic pump.
I connected a Nucleo-F429ZI to the MP6602 demo board

My application need freq goes from 0Hz up to freq_work with ramp acceleration, 1 sec.
freq_work can be setted in a range from 7kz up to 14kz.

I have several strange issue.
for instance:
freq 14K , bes=2 , sth=1, beg=6 i have 36% fault , bemf varing from 0 to 190 but motor is running.
if i disconnect the motor i got bemf fixed at 128, and no fault … but the motor is disconneted!!!
I read and program the mp6602 register by spi.

I read MP6602GV. pdf 10/28/2022 and also MP6602 AN189 Configuration.pdf 8/2/2022

Any help apreciated, any drive example in c with a well tuned stall detect
Thancks