Premium accounts are fee based and limited to specific countries. Happy to provide more details if you need it but first, you'll have to be from a country they're willing to sell to.
We are in Thailand. We are trying to develop a way to send a URL of a document to various users via the LINE messaging API. But we don't have User ID, only LINE ID. So, I created a BOT, but need a verified account to use the API in retrieving the User ID from the profile. If getting a Premium account will automatically be a verified account, then that is what we need, but I'm not sure if it works that way.