payment not allocated

I have made an EFT transfer for my mother to her RCS account because I am the one paying her account and she doesn't have an email address. I have used the details as provided on the statement as to how i should pay via EFT, to my surprise, my mother was told the payment is not reflecting on their system, we have called several times with no success, i have no proof of payment but RCS failed to use the account I gave them to locate the payment done on the 28/02/2015. Some agent even refused to assist any further if we don't have the proof of payment after I advised him the payment could be in their default account. I need this rectified immediately, or i'll take the matter to ombudsman. For any further details, contact me.