I think it has been said already but just in case, you have to cough up an extra £2.50 for Blackberry services.
I have no idea why as i have never been tempted to own a blackberry handset.
I see it every time i top up, that BB users need to purchase a BB add on.
Your £5 goodybag will not include that, it has to be bought from the BB goodbag menu or bought separately from airtime credit or using a payment card.
Bad news is, because you have a goodybag active, you will not be able to activate a new plan until your current goodybag expires :-(