They are apart of Provident Financial and their number is 01274 731111.

The chances are that the NGN will route to a call centre that deals with card enquiries from other credit/debit card companies as well as Provident's own Vanquis card.

I'd try the geographical above but failing that it may be hard to get the real geographical alternative.

Here is their website.

Let us know how you get on.

Agreed with bbb.
Goto www.192.com and do a search of the postcode BD1 2LQ

As well as 731111, a few other numbers come up.
Don't bother with the Chatham address, it's just a PO box

Edit
Without meaning to pry into your financial affairs, I would suggest you look at the rate of interest before taking the card. 39% APR is daylight robbery. IF your credit rating is low, and you require a credit card then could I suggest you look at the new breed of cards that operate on a prepay basis.
Unless things have changed, friends of mine who have had the need of Provident's services have never found their credit status improved. Perhaps they use their own credit register.

Vanquis Card have bad press reports that you may want to have a look at:

http://www.thisismoney.co.uk/money-savers/article.html?in_article_id=320595&in_p...

http://forums.moneysavingexpert.com/showthread.html?t=505861

Their address is a P O Box number from which their geographic number cannot be deduced:

Vanquis Card
Customer Services
PO Box 399
Chatham
ME4 4WQ

There used to be a Chatham geographic number for them, 01634 793 500, but it has been made public on the Moneysavingexpert.com website and if you call this number now the phone just rings and nobody answers. I expect this is deliberate.

Vanquis are part of Provident Financial, who are in Bradford.  You could try their number 01274 731111 to see if they can transfer you. If they are reluctant to do so tell them that 0870 numbers are barred by your switchboard. Use the 141 prefix when calling them to conceal the number you are calling from.

Have you tried the other numbers in the database?

01634 793605
01634 793609
0800 3777333