No refund after more than 5 months!! Still waiting!

I bought flight tickets from MyTrip. I bought tickets for me and my wife from Johannesburg to Lisbon with a layover in Maputo, Mozambique. The airline is LAM. A month before our flight LAM notified us that they rescheduled the flight from Maputo to Lisbon. I asked MyTrip for a refund due to the rescheduling by LAM. They cancelled our flights and confirmed that they are awaiting LAM’s approval for the refund. It is now more than 5 months later but MyTrip is still claiming that they are awaiting a refund. There are no contact details that are in service in South Africa for them Any emails to them get the same generic answers with statements like ‘rest assured’ and ‘be patient’.