I payed for something they cannot deliver, and wont refund me

So I have contacted Webafrica to see what is happening with the installation and that I already received my modem and paid for delivery R300 into webafrica's account, then I get told that webafrica is no longer coming to my area/road, it upsets me that no one thought to inform me and that I paid for something I will no longer need nor use, so my issue is webafrica wants the modem back (which is not a problem) I would appreciate if I was refunded my money seeing that we will no longer be with webafrica, this was on the 11th of January 2022. I contacted them yet again today on the 9th February 2022, they are refusing to refund my money and told me that I need to give back the router. once I asked for his boss's name and contact number they refused to give it saying there is no direct contact number. I do not know how to get through to them, I know it is only R300 but it is still my money.

please help me.