3 days early debit!

For a while my debit orders have gone off up to 3 days early. I get an sms saying that the debit order will track my account from one day before my set date. I never asked for this to be done, and I have tried deactivating it by ringing support and got confirmation that it was deactivated, but it still happened. Usually it's o.k...I get a bit irritated and I just go along with it, but this time it went of 3 days before my salary date, which removed a chunk of the money in my account supposed to last for the last 3 days of my month.

So now I am away from home on a long weekend, and the money I was relying on for petrol is gone! Big thanks for that!!!

Why would you deduct money before the set date, look at a 12 month statement or something, my debits are solid, so there is no need to try and catch the money before it goes out!!!!!!!!! This is utter ****!!!