Incorrect missing NI contribution year for 2021-22 - Trying to correct

Hi I'm trying to correct the 2021-22 year that is showing as no national insurance paid but I did pay. All other years are correct including 2022-23. I have sent in two letters with evidence from HRMC that it was paid. The first letter was sent over 7 months ago and it hasn't been corrected. I am self-employed. The letters were sent to Individuals Caseworker, National Insurance Contributions and Employers Office, HM Revenue and Customs, BX9 1AN Anybody else in the same situation or has any advise? I haven't tried to call 03002003500 yet, should I? Many thanks 

Name removed admin 

Hi Phil Carter,
Our Individuals Caseworker Team are currently dealing with queries received in January 2023 so there may be still a delay for you to receive a reply. However, you may wish to call our National Insurance Helpline on 0300 200 3500 to make sure that we have all the information that we need to trace the missing contributions and record them to your National Insurance account.
Thank you.