Nedbank does not help customers financially

I am heavily disappointed in Nedbank, first thing I was phoned by customer care after using HeyNed where I inquired what credit bereus does Nedbank use and what must my credit score be at least, because all credit bereus informed me on there apps and sites I need to get a vredit card to improve my score as it improves my credit mix. So my score differs on XDS, Transunion, Experian and Compuscan but no adverse items listed and the score is good on some and average on others. so after not getting an answer I just had to apply for a credit card as nedbank cant tell me the credit bereu used or what my score must be atleast. I told the agent handeling the application I want to apply for credit card to improve my score and proof my credit worthyness, any how i was declined and appealled the outcome just to get a decline message my score is to low, but again no indication what to work for on my score and having a platinum account with Nedbank for over an year and making timeous payments on my loan. How on earth must I improve my score if Nedbank cant even help me get a credit card???