Openreach Database

Hi all, i wonder if anyone out there can give me some advice.

I currently dont have broadband or a phone line for that matter.
I want to get a new line and broadband with talk talk, so i phone them up and everythings going great, until they access bt's openreach engineer database to arrange for an engineer to do the work.
Thier system says my address dosnt exist! So because of this, they cannot proceed any further because they have no way of over riding bt's system.

My address is registered with the land registry, and comes up fine thru the post office, yet BT Openreachs system thinks i dont exist! Plus openreach isnt a 'public facing' company, so i cant simply contact them as they dont deal with the general public!

Any advice on how i can proceed appreciated!
I dont wanna take out a line with BT.

Ollie