Do you have the latest BIOS/UEFI and Motherboard CHIPSET versions installed from here:
BIOS: Support For X470 GAMING PRO MAX | Motherboard - The world leader in motherboard design | MSI Global
Motherboard CHIPSET:
Or from AMD Download page for your X470 CHIPSET latest driver (2020): https://www.amd.com/en/support/chipsets/amd-socket-am4/x470 :https://www.amd.com/en/support/chipsets/amd-socket-am4/x470
Try resetting your BIOS/UEFI to Default by doing a CMOS CLEAR (removing motherboard battery). Follow your Motherboard's instructions on doing a CMOS CLEAR.
Then see if your Ryzen is being correctly recognized in Windows.
If after installing the latest BIOS/UEFI an CHIPSET version and still Windows is not correctly identifying your Rzyen then you probably going to have to do a Clean Windows install as a couple of Users and one Moderator suggests after upgrading to a Ryzen processor.