They will take the full cost of your remaining contract.
@Emilie1 I'm astounded that you haven't been disconnected for non-payment.
You need to speak to the Payment Management Team on 0800 902 0217.
The opening times are:
Monday to Friday – 8am to 8pm
Saturday – 8am to 6pm
Sunday – 9am to 6pm
Best chance of getting through is calling at 8 am
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