Corporation tax - unallocated payment

HMRC have not allocated 2 instalments of our Corp tax for y/e Jan 23 even though we paid using the same reference as we used to do. I made several calls and was assured it will be investigated and we will be contacted if any further issues. Today our accountants found out that payments are still showing online as outstanding?? And we still have not received any notification since Dec 23! Getting through on a call takes ages - already 30 mins on a call and no answer...

Hi 
We are unable to answer queries of this nature on this public forum as we would require utr and payment details.
In general, you should ensure that the correct payment reference (which changes slightly each year depending on the accounting period) is used.  
You may wish to contact us in writing at Corporation Tax Services, HM Revenue and Customs, BX9 1AX.  
Thank you.