Worst customer service

Last year March 2020 my return ticket from Paris was cancelled and I had to buy a new ticket back to South Africa before the National Lockdown. I received an email from Travelstart about a refund for the part of the ticket been cancelled. From March last year I'm still waiting for feedback and Travelstart don't reply back to my emails. I've requested a voucher of the airline and the terms was to use it before the end of March 2021 but I did not receive any voucher yet and will loose my ticket voucher, I've then asked for money refund and now Travelstart just don't asnwer my emails.