PAYE coding notices for tax year 2023/24 missing

Hello, I'm filing my tax return, and there are some fields that require checking the coding notices. Unfortunately, they are not available on the site (like I have for the 2024-25 year, for example). I posted a letter to HMRC requesting these notes. The status now shows as "Completed," but nothing has changed, and I have not received a response. I really need these notes as I also don't understand why I don't have any personal allowance for 2023-24. My salary didn’t exceed the threshold, so I would at least like to see an explanation. Where should I request this information again? Thank you

Hi,
Unfortunately, it is not possible to check individual tax records through this forum, if you have a question which relates to your personal tax situation or tax code
please contact our Income Tax team:  Income Tax: general enquiries
Thank you.

I already did contact - I sent the letter. After some time the status was updated to "Completed", but I did not received any information or letter with notes. Could you please advise on the next steps I should take, or if it would be appropriate to raise a formal complaint at this stage?

Hi,
Unfortunately we can only answer general enquiries on the forum and would need access to your tax records to advise you further.
If you contact the helpline we can review the outcome of your letter. Contact HMRC
Thank you.

Got it, I'll try. Thank you