Hi Lamby,
I work for Vodafone and can offer you some informal help.
The Outgoing call barring codes are:
ACTIVATE: * 33 * Barring Code # Send
CANCEL: # 33 * Barring Code # Send
INTERROGATE: * # 33 # Send
Personally, I wouldn’t try the 1919 code as this may be different and you don’t want to block all calls.
If you’re unsure, you should contact Vodafone through their website at
www.vodafone.co.uk/contactus. If you type the code FIT135 in the main body of the email, it will be routed to the most suitable person.
I hope this helps.