If you have done a complete reinstall the issue is likely faulting hardware or incompatible device drivers.
I would suggest testing any HDDs with SeaTools for Windows, and testing your RAM with Memtest86.
You could also check to see what drivers are available from you device manufacturer; for...
The latest BIOS was only released a week ago, maybe it has a bug!
MSI are currently only offering the chipset driver version 6.10.22.027 from 2024-11-05 - this could mean that later drivers have not been sanctioned for use with this board.
Simply disconnecting the drive(s) should enable you to access the BIOS.
Alternatively, if you boot from a Windows 10/11 USB you can access the Windows Recovery Environment and go to Troubleshoot > Advanced options > UEFI Firmware Settings.
Creating or using another user profile might be worth ago.
I would maybe query your SSD's with the diagnostic tool or maybe use Perfmon to generate a System Diagnostics report (this will query SMART).
Does the issue occur when using Cut in a text document (i.e. cutting and pasting text, not files)? If so, it sounds likely to be an issue with the clipboard.
Is there not an option in the top right to sign out of the current/old account?
Also, you might have the other MS account linked to other Microsoft apps, such as OneDrive, Office, or Skype.