Refund

Good day

I took a loan with Capitec bank last year beginning of the year and that time I was banking with them so now I changed the bank to FNB recently I did provide them with my FNB bank details gave them authority to debit and did notify them my salary is no longer paid to them anymore. I happened for me to be in arrears with a month so now the due date for my monthly is the 19th so now yesterday I had funds in my capitec account which was less thn the installment so now capitec debited those funds, I called in trying to find out why did they debit on my capitec whereas I gave them authority to debit on my FNB account they told me they do have right because m in arrears with my loan so am asking the how can they have my 2 bank account on their side how can they use 2 bank account for one client coz I did tell them am getting paid to FNB now and what I want to know is every financial institution must do debit check and collections department need to call client when there's arrears before they debit but no one called me and I called my self was transferred to collection and the lady said they cant refund me and I called complains department and I was speaking to Viwe Bokveldt and reference number for my query is ********** 7 so he advise me the same thing no refund am in arrears . I went to the Bank in Wynberg branch I spoke to Felicia branch manager and she said I was supposed to be called regarding the arrears but they didn't and she showed me section 11.1-11.2 that state "all amount owing to us in terms of this agreement will immediately be due and payable without notice and /or without detracting from any other right and remedies we have under this agreement or by law we may transfer any amount owing (ofwhich they debited less th from your capitec savings account" so I asked them to show me the section that says they do have a right to use more than one bank account for one client no body answered me and and asked them to show me the section that said if they don't receive funds on my external account they can go to my capitec with out contacting me, instead of giving me an answer they just ask if I was to make further arrangement coz the money that they deducted was less than the required amount. to rap it up my consent or complain is that they using 2 bank deatils for one client collections department didnt contact me first to find out the reason for defaul on FNB and I want refund then I can make arrangement to pay my arrears

Thank you