FNB Tell you your money's on it's way and then renege on the agreement

I have been a client of FNB for over 7 years and I app**** for a loan as a new business owner I needed a laptop. The loan was approved via the app and I have screenshots to say that the money is on it's way to my account. They then said they needed proof of income, which I duly sent from my auditor (as I'm a business owner) with proof of income, apparently that's not good enough now. I am also a Private Clients member, so I pay a fee for a private banker. I have called the department 8 times and all I get is music, not even a voice to say i'm through to FNB. How can you commit in writing by saying "your loan is on its way and you'll get a notification when its deposit to then decline it 3 days later after that money has been allocated to the need it served. Is that even legal????