Waiting over a month for a refund

Already waiting over a month for a R999 refund even after I cancelled the service and returned a modem they sent before the fibre line was even installed.

Absolutely horrific customer service as the call centre staff tell me a refund has been processed, and the next time I phone them they say there's no evidence of any refund being processed, and that they will process it now, which they never seem to do.