Stalls when stopping at stop lights?

When you come to a stop at lights or traffic the Eco mode kicks in, usually it keeps idle and low rev. But now it just stalls the car and every light on dash lights up and alarms, car states to turn off and restart car manually, no faults listed, had diagnostic and no faults listed, have a new battery and still has same issue. Car rounds fine when Eco mode is switched off.

2017 Ds automobiles ds4 1.6ltr bluhdi.