No output change with 5A current sensor

Hi everyone,

I have a hard time to output the correct value from the 5A ac/dc current sensor (ACS70331). I feed 3.3V to the vcc and I try to mesure a servomotor running on 5v. The load on the servo is between 1A and 3A, but the sensor always output about 1.5V on the output pin I assume it was my vref). I read it with a ESP32 and a multimeter.

The 5v power supplier is directly connect to the sensor + and the sensor - to the + of the servomotor.

I have also a 2.5a sensor that is working well and I plug it with the same connector to test.

Any idea what the issue can be?
Regards