FNB- how can we ***** you? its time to "switch " from FNB

I have had two, month to month sims, or so it was advertised.. I wanted to cancel them I phoned FNB at the END OF APRIL , the staff member told me to give notice at the beginning of May, and I WONT BE DEBITED. So I gave notice the beginning of May. I was debited for both lines the end of MAY and for one sim end of June. I would like to point out that advertising a month to month sim where you have to give three month notice is FALSE ADVERTISING. In addition, I have spoken to FNB at least 10 times. Thabiseng assisted me. When I say assisted, she insisted that FNB is within their rights to keep debiting my and oh they just conveniently cant find the recording of the phone call with the staff member who told me when/how to give notice, even though the calls are recorded, but they can find a bunch of documents and quote to me how they are withing their rights to do this and take that from you. FNB, how can we ***** you? Its time to "switch"