Self Assessment registration deadline

I have registered online for requesting the UTR for self assessment before the deadline (3 October 2023) and received the reply today indicated the application is rejected (Personal detail is mismatch with the HMRC record) Do anybody know if I resubmitt again, will it count as "Late submission" and will be fined? Also it is a little confuse for the regsiatration Take it as a example: The full name is Tai Man Chan (Fake name) The PTA will show only Tai Chan Then I should submitt as Tai Man or only Tai, I guess it is the issue for the personal details mismatch...... Hope there is some body have the advice for me. Thanks.

Hi BravoHKer,
If you are not able to register online due to the mismatch then you will need to contact HMRC to review and register. Self Assessment: general enquiries.
If you register after 5 October 2023 for the 2022/23 tax year once set up you will get 3 months and a week to file the Self Assessment tax return before late filing penalties are charged. 
Thank you.

‘If you register after 5 October 2023 for the 2022/23 tax year once set up you will get 3 months and a week to file the Self Assessment tax return before late filing penalties are charged. ‘. So would there be no penalties at all for late registration if the return is filed before the extension deadline and any tax due is paid ?

Thanks. I finally get in chat with the online advisor and with the help from them, the UTR was successful registered and issue for the Self Assessment purpose.

Feedback .

Hi Lottie93,

The 3 months applies to the filing of the tax return and if filed within that time then no penalties would be charged.

The due date for payment of any tax due remains at 31 January 2024.

Thank  you.