Rain-billing department dragged its feet in helping solve a payment issue that was made directly to its account

Rain-billing department dragged its feet in helping solve a payment issue that was made directly to its account. Even after I was advised to email a POP, a day departed without receiving a response acknowledging receipt and or noting any progress of my inquiry. I am so annoyed with the treatment I have received from this (Rain) company in the past two days. Mandla