Just an update to mention how things went. I called NTL as soon as I could and spoke to a very understanding lady who seemed more angry than me about it since it has a apparently happened to a few customers. She said she'd sort the problem out and make sure double wasn't taken out via direct debit. As promised the correct amount was debited and I also received a very apologetic letter from NTL.
Mistakes happen in all companies of this size and I'm very grateful it was sorted out so efficiently.I know it goes against the grain to applaud NTL on here but if we're going to post the bad we should at least post the good too. Well done NTL
.