Today's afternoon sailing to Liverpool, originally delayed by over three hours, has now been cancelled.
The announcement comes as engineers were trying to fix the Manannan's faulty generator.
This morning, the fastcraft had to turn back on its way to Liverpool due to the technical problem.
The company's advising passengers who were booked to travel on the 3pm service or its 7:15 return to contact the reservations teams to arrage refunds or booking changes.
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