Their website shows a Line address, add them, discuss the issue, eventually they'll send you a link to pay, think i paid via QR code.
Below is the first website that came up on Google, see if there's a better one
https://3bbfiber3online.com/568975/?gad_source=1&gclid=CjwKCAiArKW-BhAzEiwAZhWsIOgrXH4mr7HMSum5r92__A9E6YVG_0Z9oKEsBs6iPP7ZtAMMbPQQPxoCmmoQAvD_BwE