Humiliating experience at Zone Fitness Cape Quarter

i have been a member of Zone fitness for more than 2 years now, yesterday morning when i got to the gym i was practically detained by a staff member over an alleged payment , who demanded that i make a payment right there and there even though I was not in arrears as the fee is debited and when i told her this she proceeded to look through my profile and said I missed many payment , even though you can't go to the gym in arrears as you are not able to gain entry I was left humiliated and angry and i wrote to zone fitness and they didn't bother to call me and now I wants to cancel my membership and not pay the cancellation fee