Credit since 2020!!!!!!

Once again I need to rate Qantas very badly, we have been struggling to get refund from Qantas since 2020 due to covid. We get different instructions each time we send mails but now no one evens answer my mail or let us know that the refund will be done. Im so frustrated, how can we struggle so long to get money back to us which me paid but once we need to get credit it doesnt happen. i do not know what to say and what to do next