What do if missed 5 Oct registration date for self-assessment online Jan 31 deadline 2023

Hi, I would like to complete an online self assessment form for 22/23, but I've just discovered that I've missed the 5 October deadline for registration for self-assessment. I have rang HMRC for advice but the auto system won't let me wait in a queue and instead just cuts me off. Can anyone provide any advice on what to do now? Thanks

Hi

You can still register now but any tax due still has a payment date of 31/01/24 - Self Assessment tax returnsx

Thank you