extra charge without notice

[lockster0191]

hi need advice, i have the sky broadband & phone package.
my half price 12 month passed in febuary this year my payment has been £24.50.
my last payment for 25th may i left £25 in my bank for payment thought all was well, however today 1st june i receive a email saying payment has been missed.
total shock as i am on benefits so make sure payment is there so cant get any bank charge problems.
rang sky they say they have charged £3 extra for mcafee internet security.
i have not had or asked for this but while on the phone to sky they say on my application 15 month ago i ticked a box saying i would use it.
but i have never had it, now because of this my bank will now charge me £35 for a missed direct debit which i am going to really struggle to pay.
how can sky charge me extra i was not informed extra would have been taken otherwise i would have left the few extra pound in the bank.
what are my options, while on the phone to sky they were really unhelpful they said they would give me a credit of £15 for my account & if i send them them my bank statement to say charge for missed direct debit they may or may not credit me this.
like i said as far as i was aware i had left enough in my bank to cover my payment how am i supposed to know 15mnth later i ticked a box about internet security.
thanks for any advice

[seawright]

I know it is always easy to be wise after the event but each month Sky produce a bill ten days before a request for payment is passed to your bank. You would have been informed of this when the direct debit was first set up. As Sky no longer routinely produce paper bills you would need to check the bill online or using the interactive services on your TV if the Sky box is connected to a working telephone line. This way you would know how much was going to be taken out of your bank account each month and have the opportunity to dispute the amount or ensure that sufficient funds were available.