NO refund received from TAAG Angola Airlines

I was suppose to fly back from South Africa to Portugal in March 2019, however due to covid,this flight never happened. I eventually 3 months later flew back to Portugal with KLM/AirFrance on a repatriation flight. Once I was back in Portugal, I contacted my Travel Agent - Thompsons Travel and requested them to request my refund from TAAG, for the flight that was not used. The send numerous emails to TAAG Customer Care, I send numerous emails to TAAG Customer Care. Yet to date, which is 21 October 2022, i have not received any refund for this flight that was never used. The travel agency also does not receive a response from TAAG. I will accept to just loose this money, as the repatriation flight i was forced to take, myself and my daughter cost me R50000.