In order to activate B2B you need the latest version of the plugin(2.2.6)
Woocommerce -> Settings -> Checkout -> Klarna Checkout ->
Allowed Customer Types to B2C & B2B or B2B & B2C depending on which checkout you want to show first.
You need to have KCO B2B activated on your account, to apply visit this page:
https://www.klarna.com/se/foretag/klarna-checkout/klarna-checkout-foretag-form
