You should have had a schedule of payments stating when the DD payments would be taken and the amounts for each one sent when the DD was set up.
You need to check that the ref number showing on the bank statement matches the number on th schedule of payments they sent to you when they set up the DD. If they match fine; if not, you have a problem.
I don't think it is legal under the LGFA 1992 to send you a summons before having sent you a reminder for non payment, so see if you have had a reminder. Problem is that the Council doesn't have to prove that they were received, just that they were sent.
Go to the Council, show the bank statements and the DD coming out, and ask them to stop the Summons; delete the costs from your account; and trace the money (which hopefully have been taken as per the DD schedule of payments) as they have cocked up. Get the person you see to give you their name and extension number so that you can chase them if necessary.
Last thought - if you are a f/t student, have you applied for a 25% discount? If not, do so asap, as this will reduce the bill further. If your dp is about to be made redundant, ensure that you apply for Council Tax benefit as well, as that will reduce the bill even more.
Hope that helps - but don't leave it until the court date as not only will you get the costs of the summons, you'll get the Liability Order costs as well, as it's a hassle taking them off an account. Best to get it sorted beforehand.
The Scaryteacher formerly the Scary Council Tax Officer!