Hello,
Thank you for your question. In regards to getting an NP code for your Vegas mobile, it would seem that your phone is locked. This means, in other words, that the mobile phone you have purchased is only designed to accept a certain SIM from a certain network, e.g. T-mobile, orange etc. If another network SIM is inserted into this phone, it will not work and will ask for an NP code.
With that being said, you can use the internet to search for an NP code, which you can usually find for free.
The other option is to take your phone to be unlocked. Depending on where you live, you will not have to travel far to get this done, as this is a popular request and is done in many shops. It will cost you no more than 10-20 £/$. This may be the easiest, most effective and quickest option for you.
I hope this helps.