DC motor on I2C Motor Driver(L298): PWM is 25Hz and can’t be changed

Products & Technology Grove
25

Motor.frequence(50) is not possible with Grove_I2C_Motor_Driver_v1_3
According to the library:

/**************Prescaler Frequence***********/
#define F_31372Hz                 0x01
#define F_3921Hz                  0x02
#define F_490Hz                   0x03
#define F_122Hz                   0x04
#define F_30Hz                    0x05

and


if (_frequence < F_31372Hz || _frequence > F_30Hz) {
		Serial.println("frequence error! Must be F_31372Hz, F_3921Hz, F_490Hz, F_122Hz, F_30Hz");
		return;

So 50 in Motor.frequence(50) is not a valid argument because only 0x01,0x02, 0x03, 0x04 and 0x05 are valid.