VAT QuickFile submission error messages - double submission

I submitted my VAT return by QuickFile on the 7 December and received an error message. Rolled back and resubmitted a couple of times. Apparently there were problems that day. Have tried to resubmit return numerous times since then, on 27 December, 28, and today. The error message now is double submission. QuickFile says this implied that HMRC have received submission. However, on the my VAT page it says that there is no submission for this period. Impossible to get information online or by phone. The return is due by 7 January and I have been trying to do it for a month without success.

Hi,
We are aware of an IT issue that has prevented a number of VAT returns submitted on 7 December 2024 from being accepted on to customer,s VAT accounts.
If you have been impacted by this issue, your business tax account will show the return as due on and received on 7 December 2024, but with a penalty or penalty points applied.
We are currently taking action to correct the issue and complete these returns in the system.
We will remove any penalties or penalty points incorrectly applied as a result of this issue. You do not need to contact HMRC, or take any further action.
Thank you.