Retracting online service self-assessment to change format of submission?

Hi! I have submitted by 23/24 return using the online service, however I subsequently realised that non-residents to the UK (which I am one) aren't meant to use the online service with HMRC and instead need to get an advisor to submit a return or use an online 3rd party software. Is it possible to retract my return completely and submit with the 3rd party software? So far I can only see how you can amend your existing submission on HMRC website, but not just delete it.

Hi,
If you have already submitted the tax return online then you will be unable to retract it. If you need to submit the SA109, then you will have to download and submit a paper S109:
Self Assessment tax return forms
Thank you.