No Notification of Banking Details Changing

I received an SMS advising that I was outstanding on payments and my chronic medication not covered by Medical Aid would not be dispatched. On querying this as I have been making payments I was advised that their banking details had changed. I had not received any notification that their banking details had been amended and now have been advised that "I’m assuming you have paid it into the Standard Bank account which we’re no longer using and you either need to go to Standard bank for a reversal or speak to your bank and get the funds returned". Surely Pharmacy Direct would still keep their old Bank Account active for such cases like this. I will now be sitting without my Chronic Medication as I cannot afford a Double payment and who knows how long it will take to get this mess sorted out.