Tax due paid but now offered repayment

I have done my self assessment for 23/24 and paid the tax and National insurance due (I decided to pay early this year as it is my final year of self employment) but after logging in to my account the website is now saying that the amount I paid is an overpayment and is offering a repayment. It does not make sense as below that it is saying that the payment (amount I have already paid) is due for 23/24 by 31st January 25. I have tried to call HMRC but cannot get through, so can anyone make sense of this for me?

Hi

As the payment is not due until 31 January 2025 then the payment will show as a credit until closer to the due date and then it will be allocated. 

Thank you