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Thank you for the question and your patience. Should you still need assistance for information purposes only...
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Initially, it possibly have airlock in the pump and water intake system
Try to manually prime your machine, for instruction CLICK HERE it supports all gaggia and seaco models.
Sometimes you need to get rough on your machine in able to remove the clog air on water line. slamming the water tank into machine sometimes help. If still, unplug your machine, remove water and turn the machine upside down or shake your machine if possible.
Let me know if you still have questions.
Hope this information will be helpful.
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The problem was not an airlock. Your incorrect answer too late to be of value had it been correct as I had already resolved the problem.