Debited three 3⃣ times in one month for changing policy from business to personal and for pro rata

Debited three 3⃣ times in one month for changing policy from business to personal and for pro rata. When I request my money back I'm being asked to send a bank statement (which has private personal information not only related to the MiWay debit order) for it to be processed in 3 days and being told that otherwise I'll have to wait 7 days. Doesn't matter to them that I've never missed a stalment for over three 3⃣ years