we don't get polos in the states, so I'm curious which engine you have, which transmission, and which model year for your car.
....because my first thought was "I wonder if he has a 2019 or 2020 GTI or GLI" and, ...uh-oh.
well, you have the smaller engine (I think all Polos do?), but if it's a 2019/2020, you might have the dreaded stall that effected mostly NA GTIs and GLIs for 2019. (very few reports from the EU stock, but those cars are also built in Germany with different power ratings than what we get over here)
How is the stall happening? Does it take a while for the car to warm up, and then eventually it just soft stalls as you slow down to a stop, like you didn't even notice it until you try to get back on the throttle to start? Does it stall when in neutral--either by gearbox or with clutch down?