FNB personal loan

I have a personal loan with fnb i pay an instalment of R2043.66 monthly and I'm in arrears which I have an arrangement to pay extra R500 On top of my instalment. It's almost 7 months now every month fnb system is deducting extra different amounts on my account on top of the instalment and the arrangement I made . I am struggling to get my money back every month I should use money to get my money back. Today it's it's the 16 July since I made that request on the 30th of June and spoke to their agents they promise it will be made in the next 24 hours it's not happening. Please help me to get my R2043.65 hack into my account immediately .On the 30th June I spoke to precious who did the reversal and paid it to the cheque account which has a negative balannce and ut was drducted on an easy account but not paid back to easy account and I called again when it was not reflecting after 5days I spoke to Logan and she also promised it was done to the correct account it will be paid and Lesego called me regarding the e-mail I sent to the resolution department she said she will make it urgent it will reflect at least in Wednesday the 15th July, I called yesterday the 15th I spoke to Penelope who also said it will reflect before the end of the business day which is still not reflecting. May you please assist me I'm struggling with fnb and I'm taken from pillar to post and I don't understand who gives fnb authority to deduct unathourised debit orders in my account. I have been a client for fnb for more than 17years so it's a crime to have arrears with them. I'm not in a good standing to pay an instalment of more that R5000 a month with them when I have other credit providers to pay. Urgently attend to my query with the reference no given below and help me get money back.