Ducati MONSTER 821 2016 Owner's Manual page 162

Important
If this procedure is necessary in order to start
the vehicle, contact an Authorized Ducati Service
Center as soon as possible to fix the problem.
Note
The vehicle can be started until a Key-Off is
performed. If the problem still persists upon the next
starting attempt, repeat the procedure from the
beginning in order to start the motorcycle temporarily
again.
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