Hi and welcome to just answer.
Initially, try to fill warm water on water tank then turn the machine ON and despense hot water. Maybe your model need to press hot water button or just open the steam wand. Continie to despense until ventilate error message disappear.
If still, open the steam knob to despense hot water then while despensing try to push in the knob. If still, you have faulty steam valve or flow meter that need to replace.
Hope it helps.
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