you need to ring - 150 and follow the prompts to thinking of leaving - 1 - 4 - 4 as far as i remember on the keypad
BUT you might not get the result you hope for assuming you are looking to reduce your package price - VM give discounts the more items you have on the deals so whilst removing the land line would take that item off your bill other things would change - you might even finish up paying more
so if you dont use it then it might be cheaper to just unplug it
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Tony