Xiaomi Scooter 5 Elite - Brake system help

Hi there.

I bought a Xiaomi Scooter 5 Elite from someone that was leaving the country, and even though the battery and power are still 100% healthy, I am experiencing weird issues with my brakes.

The biggest thing that alarms me is the following two factors:

1. When braking, the rear e-abs always kicks in, and has a loud whistle. The braking is always very sudden when the e-abs kicks in.
2. On a light downhill, when the speed is too slow for the e-abs to kick in, the scooter doesn't stop fully.

There are no sounds coming from the front brakes, and I even tightened the whole system by using the bottom scew at the front drum brake. The brake line tension is not the issue.

The scooter is supposed to be 6 months old, so I doubt that anything has worn down, or maybe it has? I am not entirely sure what to do, however, my next step would be to take it to a professional escooter repairman.

Lastly, on flat surfaces, the scooter does brake fine, but it makes the loud noise in the rear almost always. I am 80kg, so it should be able to handle me fine.

Thanks for reading