Bunch of ******* who takes your money but provides no service

My router was delivered on 23/3 on 25/3 the engineer came to install an outdoor router but when he was done they realised there was an issue on Rain's side with my account and the sim was assigned to another account. He gave a new sim and said it would be provisioned by the Monday. By the Thursday it still wasn't and I requested Rain to come fetch the router and refund my money. On the 30th the same engineer came and removed the device, yet I still have not received my refund and keep on getting sms's from the courier wanting to come fetch the router. I want my refund as I did not have 1 second of connectivity from Rain.