Do you have the game installed on the C drive (same drive as your OS) if you don't, I would completely uninstall and reinstall on the C drive.
Usually those DX errors pop up after certain game files get corrupted, usually related to the drive the game is installed on not being C, but a secondary or external drive being used.

You can try installing the game in the Program Files folder (if the x86 version folder still gives this error), or install the game directly on to the C drive "This PC > Windows > Here" for example.
If you still get the errors, I would test by installing on a different drive, even an external drive and see if it makes any difference at all.