POOR SERVICE!

i app**** for a personal loan via my banking app, i received an sms that the loan was approved and the funds were paid into my account. i spent some of the loan money and the balance was transferred to my savings pocket. the following day when i logged in to my app i found that my main account was in excess and i immediately contacted FNB, i was told to contact their collections department for my query to be resolved. i did contact them & i was told my query will be escalated to a team leader to call me back, i did not receive any feedback from the team leader i called FNB again i was told it was an error the loan wasn't supposed to be paid to my account and i should pay it back. bear in mind that i did not receive any communication about their technical problems, now i'm sitting with an account that's in excess and i won't be able to pay back the loan in full now so i asked them to approve my application and allow me continue with my instalments over 6 months as stated on the agreement i was sent when i app****. but i'm told its not possible they want the money back. I'm expecting money on my account this evening for my cousin's funeral, i'm afraid when the money is deposited it will go towards the balance i owe to them and this is money i have to use tomorrow. i tried reasoning with the consultant i spoke to but she blatantly told me i must pay the loan back immediately. why must i now suffer for FNB's negligence, we have a funeral this coming Saturday i need the balance of the loan i received as well as the money that will be deposited into my account tonight for funeral arrangements. FNB didn't even take the initiative to contact and let me know it was an error, i was under the impression that my loan was approved and i was eligible to receive it