Cancellation of Direct Debit to old supplier

I have never switched companies before so this is a first for me, I cancelled my direct debit with my bank last week for my old supplier. They have then sent me messages to say that they tried to take the Direct Debit and it didn’t go through and I have now received a letter today to say the same and that I have to pay the monthly amount by 11th December and they have put a charge on the next bill for a late direct debit. Should I have not cancelled the direct debit just yet and should I have paid at the end of November when it was due?

These answers from the Help FAQ should be of assistance:

Also lots of other topics in the FAQ you might like to read up on, liked from the “Help” button at the top of the page.

@Sarahemery

With any direct debit, to which ever company, if you inform your bank to cancel a DD you need to tell the company, which you have the DD setup, that you have cancelled it and you will pay any outstanding bill upon receipt of an invoice/bill.

Rule of thumb with DD, if your going to cancel it you need to inform all parties involved, the Bank and with the Company that the DD is setup.

You could be getting the notifications due to an automatic process, and that the process doesn’t take into account the switching to Bulb.
With regard to DD charges, as it was your final bill you could ask them to waive the charge due to the circumstances. As always in these type of situation contact your previous supplier and discuss it with them.