FNB Housing Finance Complaint

I am now at my wits end. I have been trying to make a payment arrangement on my home loan with FNB. I call continuously and no one answers from the collection department. The one time I managed to get through, I was advised by the agent that they have system issues and will get someone else to contact me. I have them my story and situation and what agreement I anticipated and left my details. No one called me back. A day ago I see an unauthorized debit order for the home loan going off my account which didn’t even have sufficient funds, naturally the debit order was returned. Please note there is no mandate or agreement from me authorising this action from FNB, additionally, I have still been unable to get through to collections to put in place a payment agreement and update my financial situation. I’m currently holding since 24 mins on a call to customer services who took down all my details after I explained the situation. I still have not gone through to collections and my account issue remains unsolved. I’m frustrated and dissatisfied with how this has been handled. I’m trying to fulfil my obligation as a customer but this is not being reciprocated by FNB and a result I may have to face legal consequences when I actually did my best to pay and keep FNB abreast of any financial distress on my side.