Cordless lawnmower (Earls Colne CO6)

Greenworks Model GD40LM46SP. 40 V Cordless with 2 batteries and a charger. Mower should self propel but that doesn't work, but the mowing works perfectly OK. Approx dimensions: width 520mm; length with handle extended 1640mm; with handle folded 1116mm; max height 620mm. Quite heavy. Collect from Earls Colne. Reason for disposal - I need the self propulsion owing to my age and a slightly sloping garden.