Very bad service from ITCBA and Mpowa

i have had the worst experience with ITCBA and Mpowa finance , they kept on debiting my account even thou i had settled my account with Mpowa and when i brought it to their attention they have been of no help , their customer service and call center is the worst they have no sense of customer service, i have written endless emails with no response regarding my refund, i hope they treat their other customers better , this is the worst