Cancelation outstanding amount

This is the worst company i had to deal with in my life.

I canceled my contract in time with GYM Company Roodepoort clever enough gave them 30 days in order to cancel. The day I canceled paid my fees and I spoke to the manager or is it accounts lady who advised that I owe nothing. This was last year August 2018. So now this year June 2019 they have the nerve to call me and say I have an outstanding balance in order for my subscription to be canceled so how the heck would I know a year later?

To be honest I am so disappointed at all of this.