I'd love to see a Ducati Van!!!, but assume you meant to type Fiat Ducato Van? lol
As below, check battery in key fob is replaced for a new one and if that does not work, check the electrical contacts on the sliding side door are nice and clean. If the contacts are dirty or loose, the alarm computer thinks the door is open and fob won't work.
Rupert
January 2020
Check/replace the batteries first.
Rich
January 2020
Automatic Answer
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