Hmm. That's a Coventry number, but I'm relatively sure retentions is in Teesside - for Langley anyway.
If you have other ntl services (TV, telephone) and are outside the initial 12 months of your broadband contract, Customer Services should be able to disconnect it for you. Call 0800 052 2000, and choose Option 5. If you only have broadband, call between 9-5 and they can put you through to retentions - who will obviously try to stop you disconnecting, but can do so if you really wish.
May I ask why you want to disconnect? If you're having trouble with the service, we may be able to help.
