Registering as a sole trader

For the last few years I have no UK income but oversea incomes so that I have been filing self assessment returns using my government gateway. Starting from the next year, I may expect some UK incomes as a self employed sole trader. Do I need to open a new account to register for sole tradership? I look through this web page and it says that I can register it through my existing business tax account https://www.gov.uk/register-for-self-assessment/self-employed However, when I log in my current account, I cannot find any button to add a sole tradership?

Hello? Can someone answer this?

Hi,
You would register as Self-Employed, the UTR will stay the same.
If you have been unable to register contact us online using 'Ask HMRC Online' and ask to speak with an adviser:
Self Assessment: general enquiries
Thank you.

Hello HMRC Admin 8 , thank you for your reply. Does it mean that I should open a separate account for Self-Employed, in addition to my existing account for self assessment by using the same UTR?

Hi SKL111,
You have one UTR.
When you complete your Self Asessment tax return  you just need to tailor your return at section 3 to show the different types of income that you receive.
Thank you, 

Thank you