Hi Melliker
Welcome to the community forums
If you've not been able to find a faceplate with a Virgin Media, NTL or TeleWest logo, then this might have been removed by the previous tenant/owner of the flat. If you're renting the property, please do ask your landline or property owner or lease holder for permissions to install in the home just in case this was removed by them.
Should you then be able to go ahead, book your install with a free engineer, if only a chargeable appointment is showing online, book this as a QuickStart install and either call our pre-install team on 0800 052 1734 or get back in touch with us here and we'll both be able to convert the appointment to a manned install for you,