Which BIOS did you flash, the latest beta one? Try to flash the BIOS again, perhaps maybe with the second newest version now.
You will have to use the Flash BIOS Button:
1. Download the BIOS from the MSI support site for your board and extract it.
https://www.msi.com/Motherboard/B550M-PRO-VDH-WIFI/support
2. Take a USB stick and format it to FAT32 (it's best for it to have a size of 32 GB or less). You can also try
Rufus for formatting, as FAT32 non-bootable.
3. Rename the extracted (!) BIOS file to MSI.ROM and save it to the root of your USB flash drive / USB stick (not in a subfolder).
4. Plug the USB flash drive / USB stick that contains the MSI.ROM file into the marked Flash BIOS Port (!) on the rear I/O panel.
5. With the PC off, press the Flash BIOS Button, and the LED should start flashing for about 5-8 minutes and then the board reboots.
Anything drastically different (under a minute of flashing, or over 10 minutes of flashing) and the flashing didn't work, so you can abort and try with the next USB stick.
However, i'd also like to know all your components including PSU, maybe there is a hint somewhere as to why this happened.