rain debit my money without my concern

Last month I called rain to ask them to suspend their service because they don’t have network where I will be this month. During the month I spoke to their arrogant agent she even hang up the phone before we finished the conversation. I told her I have WhatsApp respond to show that I called she told me it’s automatic respond. Now they debited my money and I never used their service. Please help me to get my money back and cancel my deal with them