One year NIC 2 payment taken off pension forecast

Good morning, I have just checked my state pension forecast as I do twice a week as I am waiting for voluntary NIC 2 payments that I have made to be added and I have realised that my state pension forecast that was £184.19 has been reduced by £6.32 to £177.87. My husband has checked his pension forecast and the same thing has happened to him. Could someone tell me why please.

Hi,
Without being able to check your record we are unable to give a definitive reply. You will need to contact our National Insurance team for advice.
National Insurance: general enquiries
Thank you.