Rain Resusing to Refund Me

I cancelled my Rain 5G plan within 30 days and was told that their courier department would contact me within 7-10 business days to collect the router. That period lapsed and called Rain to enquire about the delay and was told they had escalated my issue; I should expect a call from courier department within 2-24 hours to confirm the collection. That also lapsed called again; and the agent assisting me refused to transfer my call to her team leader because I simply would accept that I should be the one calling when they are the ones who had not stuck to their commitm! I just want my refund Rain, so please be careful with Rain!