Asked to pay Class 3 voluntary contributions when colleagues in same situation pay Class 2

I work abroad for an international organisation. I worked in the UK immediately before moving abroad 28 years ago (for HMG in fact) and have been continuously employed abroad since then. I applied to pay voluntary contributions via CF83 and provided proof of my employment record abroad as of the date I stopped working for HMG. I have been asked to pay Class 3 contributions and I don't understand why because: (a) for the tax years 2004/5 to 2009/10 I was asked to pay Class 2 contributions and I have not changed employer since then, and (b) I have British colleagues who pay Class 2 contributions although they are in exactly the same situation (worked in the UK immediately before leaving and are working abroad). How can I ask for the decision made in my case (Class 3) to be reviewed/corrected?

Hi A Oram,
If you are employed or self-employed overseas and were normally employed or self-employed in the UK before your departure then you may be able to pay at the voluntary class 2 National Insurance rate.  As you have advised that our International Team have accepted your application at the voluntary class 3 rate then may I ask that you write in and ask them to review their decision.  You could reconfirm your employment position in your letter.  
Our postal address is:-
HM Revenue & Customs
PT Operations North East England
BX9 1AN
United Kingdom
Thank you.

Italian worked in UK for 9 years, and paid contributions for 9 years ( 1999-2009), also have three years credits, then left UK on 2009, went to work in China till now（worked in the UK immediately before leaving and are working abroad). May I known Italian nation work in China ( it is not EU country) could eligibility apply for pay voluntary contribution 2 or 3 while aboard? and each year of paying voluntary contribution 2 or 3 while aboard, how much will be benefit for the pension amount ( every week how much will be added for each year of paying vouluntary contribution, if paying contribution 2 and 3 will be benefit same amount of pension amount, Please kindly check and advise, thank you

Hi crystalj,
To apply to pay voluntary National Insurance contributions whilst overseas, please complete and return our CF83 application form after you have read leaflet NI38.
 Social Security abroad: NI38
Before applying to pay voluntary contributions please first obtain a State Pension Forecast.  
This will detail your current and future entitlement to a UK State Pension and you will be able to decide whether you wish to pay voluntary contributions.  
You may find this via Application for a State Pension forecast
Thank you.

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