Billing issues

I was trying to sort out my billing and renewals over the past few months. Today I was speaking to Customer Support but as this was not a normal query the Agent seemed to try and make the case fit her script. When it didnt she disconnected.
Ive been trying to reconnect for over two hours but there is no reply or the phone disconnects.
Does anyone know how to connect with the billing departments supervisor?

Hello,
try https://support.avast.com/contact/sales_refund/sales/?c=true

Milos