Useless service from FNB

On the 2nd of March 2020 a debit order was returned without my consent and there was more than sufficent funds in my account when this occured and then I was charged a R100 fee for this? I tried the online chat without any success as those people cannot reas then I tried calling and after being transfered from one person the next I was eventually cut off after waiting for 20min. This is unacceptable.