unsuccessful online submission of tax return

Dear admin, As I have submitted my self assessment tax return online via software but the email reply from HMRC stated that it did not pass the HMRC data check. Moreover, I have double countered check for multiple times about the credential data and personal details are correct, what should I do now? I have called helpdesk already but he asked me to call self assessment team and the self assessment team did not advise. Many thanks.

Hi schangh,
If the personal details entered do not match the details held by HMRC then you would need to contact HMRC to review and update the details to allow you to file the tax return.
You can contact HMRC here:
Self Assessment: general enquiries
Thank you. 

Hi schangh

If your details are correct and there is an issue filing your tax return online, then you will need to contact our Online Helpdesk to review Technical support with HMRC online services

Thank you