Bad Service

I send a request on 19/08/2015 to update my banking details, I also requested for confirmation that all is in order.<br> Nothing was received so I assumed all is updated! When the first of September came the old banking details was debited for the installment. Which means there was no payment made for the month of September. Now I am inconvenienced to make a double installment in October. And also part of you terms and conditions is if no payment is received no claim will be paid. I assume it won't be applicable in this case because it was not me in error! I also feel that if my name will be affected in any negative matter I will take the matter further. Your urgent feedback is required and also please confirm that my details is now updated as requested. Regards