Loan declined after being approved

I app**** for a loan on via call centre and it was approved, then I went to the branch in Protea Glen Soweto on Saturday the 18th of July 2015 to sign the loan documentations which I have at home with me, then on Monday the 20th I got an SMS to say the loan has been declined I then went back to the bank to appeal and I was told to get HR to send a letter because I didn't have a 3 months bank statement as I was on maternity leave, the letter was sent from my work place and they sent me another SMS to say it's still declined. When I phone the call centre they tell me there is nothing they can do I must reply again in 30 days.