Get Line ID of offical line account through API

Hey team

I want to be able to open a Line chat with a prefilled message for an Official Line Account (business), like the example here

https://line.me/R/oaMessage/{LINE ID}/?{text_message}	Opens the chat screen with the LINE Official Account. Set text messages in {text_message} that users can send to their friends or to your LINE Official Account.

I have the access key, access token, and user id of the account, but I cannot see how to programmatically get the Line ID (ie the @linedevelopers) part through the API.

I can see the Line ID in the console (under Bot -> Bot basic ID), but I need to get it through the API. Is this possible? Or if not, is there another way to open a chat with a pre-filled message to an official business account using the UserID?

Kind regards

Jen