Looking for extra stress, take a loan with RCS

I took a loan with RCS and I paid the full amount in May, however they continued debiting from my account even though they sent e-mail confirming the settlement. I contacted them in July and they promised me to investigate, until now nothing has been done. I phoned their call center 3 times today (03 September), the first consultant said I'll be paid after 4 days, an hour later I called and was told on the 12th of September and the last one (Na****a) told me that I need to send them my bank statement, when I asked who is going to pay for the statement I was told it's their company policy, if I want my refund I should send the statement. RCS you've been debiting from my account why don't you refund the money into the same account you stole money from? This is *******, your very angry customer