StandardBank with their poor service and ********** schemes

I've been using standard Bank since i was a student till now, my 9 years old daughter is also having an account with them but I'm ready to cut the ties between me and them and i will even cancell my policies with them if i had to, my late mother had an account with them apparently the account was closed few years back but it had an amount of R8474, we did go to standard bank to ask her bank statement we were told to get the authority letter from the masters office for us to get the statement, we got the letter of authority&we were given the statement with the balance u've just mentioned, when we submit everything to bank claiming the money, o got the email saying my mother's account was closed with 0.00 balance, my question is what 0.00 balance coz we got her statement from the branch with the balance&we even got the letter of authority saying the bank must pay the amount to the nominated beneficiary, is this how they operate? Close their client's accounts&make the money dissapear? If they don't find the solution to this problem of theirs then I'm taking my businesse elsewhere with my family&everyone i know banking with them.. And i want the explanation of where the money that is showing on the statement dissapeared to