COVER DATE CHANGED BUT STILL DEBITED

I had decided to join Bonitas in October 2020 and was given the confirmation letter. It was mid October and i was was told that the full amount will be debited. Then on 27/10/2020 i had sent a request via e-mail to have the cover date changed to 1st December 2020. On 30/10/2000 i received a SMS stating that my cover date was changed from 1/10/2020 to 01/12/2020. I was later given the new confirmation of cover. So i knew that i will not be debited until 1/12/2020 but on 03/11/2020 Bonitas tried to debit me twice and there was not enough funds in my account. i had just enough for my insurance my bank had charged me twice R110 and this was taken from the money that was kept for my insurance. So my insurance had bounced and another R110 was charged by my bank for insufficient funds. Now i have a negative credit record and have been charged R330. I sent a message to bonitas and was contacted by Lorainnne Kgapula from credit control and she had told me that there was nothing that could be done as the 23rd of every month was the cut off for stopping debits. I then explained to her that this was not mentioned to me and someone should have seen that a new member in the same month had requested a change in cover date will not be expected to pay in the month that i wanted to change from. This does not make sense! Bonitas should have told me that the payment was sent to the bank so that i need to get my bank to stop the debit. My member number is ***. I was with with Momentum and paying a bit extra but with no hassels. I think i should go back to the tried and tested.