Child benefit NI credits when working

I have a child aged 12. I have been working for the last 18 years in a job. I have 18 years NI contribution paid in full from my workplace. I know you get NI child benefit credits for a child until they reach the age of 12. In terms of child benefit, I claimed for a few years, then my earnings went over £50k, so I stopped it. My question is: do the NI credits for my child get added on top of my existing 18 years? So do I have 18+12 = 30 years of NI contribution paid in full? Or do they not get added?

[Dispaly name amended]

Hi o.zorlu1984,
You receive National Insurance (NI) credits from child benefit up until your youngest child is 12 years old, whilst claiming child benefit.
If you already have fully qualifying years through your employment, the (NI) )credits received for the same years will not increase the amount of years you have.
For example if you were employed for a particular tax year and paid enough class one National Insurance contributions to make that year count towards your pension, and also received NI credits from child benefit, this would still equal 1 qualifying year.
You can check your National Insurance records online to see how many qualifying years you currently have - Check your National Insurance record
Thank you.