Nedbank took back my overdraft facility- Absolutely sick behaviour

So lastnight i used the Nedbank app and there was an offer for an overdraft with a personalised interest rate. I did the application on the Money app and within minutes R24000 was deposited to my cheque account. The money was available. This morning when i checked, the money was gone, it looks like the bank took back the overdraft. What is even more shocking and ********* is that i was told that there was no overdraft facility and the bank has no record of the application. So i was told i can apply again and held on for over 20 mins and no answer. Helped by different chat agaents and had to tell them the same story over and over again. How can the bank make the funds avaible and then say there is no trace of an application, how is that even possible. This is horrifying, and downright scarey. So money is just going into accoubts and disapearing? Lastnight i could have moved that entire R24000 to a savings account if i wanted to, the money was there. The bank should hire a forensic investigator to verify my claim if they cant see anything. If the money was in the account, where is it now, and why is there no way to trace it? Surely some investigation has to be conducted. What the hell is going on there???