Moving of my debit order date

Two weeks ago i contacted ADT and spoke to the accounts dept.. Since i am changing jobs i needed to move my debit order date from the 26th June to the 1st July. This is because i will be paid on the last day of the month. I was assisted on your system and in a matter of minutes i was told the debit order date had been moved. <br> On Saturday the 27th June, i get an sms notification notifying me the debit has gone off !!!! I would like a response from Adt.. After all i followed procedures???