Debit order query

My name is Nyalleng Moahlodi I am writing this letter to complain about the poor service provided by First National Bank. I have called their contact Centre to inquire about the change of debit order date .Debit order form was sent to me i completed the form and send it with the required documents to the email provided on the form and the other one provided by the consultant(***)I even went to their branch at Maponya mall and i was advised that they are not dealing with home loans queries. The process started on the 08/11/2022 till to date the request is not done. I have been calling FNB everyday to check the status of my request and I get different feedback from different consultants everyday. The query was escalated to admin department and i have not yet receive feedback. When I ask to speak to the supervisor or the manager i am told they are not on the floor to take my call. Today I was advise to go to the nearest branch to complete the form again, the branch where i was told i cannot be assist. I don't know what to do anymore or maybe i should move my home loan to another bank cause I am not getting the service i deserve as a customer. I am frustrated cause this is affecting my credit record .