Change LCD brightness dinamically

Hello,

in our HMI application, we need to dinamically change the LCD brightness (e.g. inside a Setup Menu). At every increasing/decreasing brightness event, I call the g_pwm_backlight.p_api->dutyCycleSet function as follows:

g_pwm_backlight.p_api->dutyCycleSet(g_pwm_backlight.p_ctrl, brightness_level, TIMER_PWM_UNIT_PERCENT, 0);

where brightness_level is a uint8_t variable with values between 10 and 100.

The probelm is that it seems that call has no effect: the brightness of the LCD does not change. Is there something I am missing?

Thank you in advance.