Individual Caseworker (BX9 1AN) contact details? (NI record omission)

It appears that the only way to contact this department (National insurance Contributions & Employers Office) to query NI record error is by letter. Is there a telephone or email contact? My two letters (and supporting documentation) have not received a response yet and I would like the records to be corrected to ensure my pension is paid in full from day one.

Hi Brian Johnston,

I am sorry that you have not had a reply to your correspondence.  
Our Individuals Caseworker are currently processing post received on 25th September 2022.
Our National Insurance helpline is 0300 200 3500 
We do not deal with general enquiries via email as HMRC do not deem email as a secure method of communication.

Thank you.

I wrote to the individual case worker BX9 1AN dated 8 February 2024 but have not received any response. I tried calling the national insurance helpline on 0300 200 3500 but the recorded messenger cuts me off each time. I am elderly and really need to speak to an HMRC human person before it's too late for me, can HMRC please help and provide me with a telephone number that reaches a human person? thank you

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Hi christinacosta,
Sorry for the problems that you’re experiencing in trying to call us.  I can confirm that our National Insurance Helpline number is 0300 200 3500.  Our lines open at 8 am Monday to Friday and if you could call as early as possible after this then you should be able to get through more quickly.
Unfortunately, our Individual Caseworker Team are currently only dealing with queries received in August 2023 at the minute so there will be a delay before they reply to you.
Thank you.