Humboldt Seeds were closed down in 2020, as were Dinafem by the Spanish authorities for contravening laws regarding cultivation tutorials.
Humboldt were a company owned by Dinafem and both operated out of Spain.
Yes, American by name, but Spanish in reality.
Any seeds still out there would be from 2020 or earlier, so be aware.
en.seedfinder.eu is a fantastic web resource and list all shops that still have stocks as well as prices.
Site can be a bit tricky to navigate, but once sussed out, is pretty straight forward.