Dismissive Customer Service and Non-existent Refund Process

I have been in a multiple month ordeal with Rain. After double debiting my account and refusing to give me a refund, they then subsequently tried to incorrectly debit my account again the this month despite still having a credit on my account from their previous double debit. (Mind you, this was after they had promised to refund me and email me the relevant refund forms, only to be left on read, seen and heard, up until the point where I just accepted that the extra debit would just have to be a credit on my account for April's bill).

I then tried to call their call center where the telesales agent was dismissive and tried to gaslight me into believing that I had in fact been debited correctly - despite their claims of a "post-paid system" and clear proof of payments for the same dates. I am disappointed and frustrated, and would just like straightforward and honest assistance asseblief tog!