I have been trying to change my banking details for my debit order for 2 weeks now

I have been trying to change my banking details for my debit order for 2 weeks now. I tried to do it on they app I was told to go into the shop I go to the shop they said no they can't do it they will do it on our behalf. Now I get a msg that they can't change it to the 3rd party (my wifes bank account) due to personal reasons I will be closing my personal account and arranged that the debit order will go off of my wifes account. I have said I can them rather pay them via EFT but they said no. Vodacom fibre had no problem assisting but Vodacom Mobile is refusing how does that work????