Bad service, unauthorized debit order

Paid R1000 for 5G Router, delivered within 24hours. It should have been a 4G not 5G, they promised to collect and refund 2 weeks before lock down. During lockdown RAM couriers phoned me and when I told them my address changed to 100m down the road, they could not collect at a different address. Ever since I did not sign a debit order but they keep ons deducting R999 per month wirhout authorization. I have so many reference numbers during the lockdown but no response. This is the worst service I ever received.