Vodacom did not change my banking details!!

I contacted Vodacom 2 months ago in order to change my banking details - they have still not done so and now the debit order went off my closed account!!!! I told them to change it from the 1 March 2014.<br> <br> This is completely unacceptable, I will not be liable for charges for a failed debit order if they cannot follow instructions!<br> <br> J Wasserman<br> ***<br> [Email Removed]