FNB ATM withdrawal query

good day<br> <br> I am really disappointed with the poor service from FNB regarding a query I have raised with them were I was querying a withdrawal of cash from one of their ATM but due to the ATM not having enough cash only R100.00 came out of the ATM where as I was withdrawing R400.00 and I went to their FNB branch in Carlton Centre and 1 of the employee by the surname of Nkosi who was supposed to assist me told me to bring a receipt from the ATM of which I told her the machine didn't print one but she insisted that she wont be able to help me without the receipt and I went to Daveyton branch for assistance and they told me they will escalate my query and will come with a feed back but even today my money is not refunded and no one is coming back with a feedback.