Delivered two devices in error, charged for the second device and no refund provided

Rain delivered two devices in error to me when I requested a 5g package. I contacted Rain in December 2021 to have the device retrieved and subsequently not too charge for for the device. To date, I have been charged for three months for a device I did not request, it took three months for Rain to collect the device (which was still sealed in a box) and continue to charge me for it, on top of not honouring my refund request.