Wrong invoice was sent for avg subscription. AVG assured I would get a credit & compensation. I did not receive Credit note nor anything else. I have case number & printscreens from the chat with AVG. Can someone help pls

not possible to contact AVG support. I need someone to help fix issue with invoice sent to me, it contains wrong info. On june 16, avg contacted me (chat) to fix issue with wrong invoice sent to me. The person assured I would get a credit & compensation. I did not receive Credit note nor anything else. I have case number & printscreens from the chat . There is NO possibility to get in contact with AVG to resolve issue.
Can someone help pls