Money disappears overnight without a trace from FNB current account

Was just checking to see if this only happens to my account....it has been happening for a long while....I am so upset for not leaving the bank sooner ....Yesterday I went for breakfast and transferred just R100 into my current account as it has become a necessary inconvenience of late (because money goes missing, I keep it in my savings pocket....only transfer when needed)…..Anyway, paid R68.90 at wimpy....had change left in the account ….as we speak, the R68.90 is pending and keeps bouncing as insufficient funds....note ….am being charged R8.50 everyday for failed transaction....but the trace of that R100 along with the R17 that was there to begin with is nowhere to be seen on my account and the agents don't know either...So, It really is time to leave this institution..... This has become the norm for over a year now..