My Cubase Artist packs don't appear on the MediaBay

Hello, I recently bought Cubase Artist 12 and it’s working well, though the Steinberg sample/preset packs I downloaded from the Steinberg Download Assistant (for example the Night Call Synthwave or LoFi Dreams) won’t appear in the Loops & Samples section in the MediaBay, and they won’t load from the “VST Sound” folder either.
I tried to load Cubase with an internet connection, then clicked on the Loops & Samples tab and now I can only see the pack called “EDM Toolbox”, but all the other ones are gone.
Does anybody know how to fix this?

I had a similar problem here: Mediabay not showing full installed sample libraries after 12.0.3 update - #3 by pmallett57