Rain charged me extra. I am requesting for callback but no one called me back.

I used rain's latest promotion to get 5G network. It all works fine but they charged me extra for the first month. I requested a callback to enquire about it but no one called me back. It has been 2 months and all my callback requests are unanswered. How do I get in touch with these guys? They don't have anyway to call them. Dumb customer service. F*ck this company.