Acceleration when the 206 HDI brake is released

Hello friends 2005 model 206 1.4 hdi, when I am on the brakes while driving, the car tries to accelerate without gas, sometimes doing this when idling in gear, why does it speed up on its own?

Does the vehicle supply gas to itself, but at idle, sir? after braking and pulling

Gas self-gasing does not disappear, only while driving, while driving slowly in congested traffic, it is normal for a while when I pull my foot out of the gas, then it spontaneously accelerates. It does the same when I brake and release it when it's slow.