I didn't think they could charge any more, that's why interest has gone up to 40% on most of them.
OP what happens depends on your bank, they might refuse it or might pay it. Can you extend your overdraft so the payment is paid? But if not, they'll probably just write to you and tell you they'll try again in a few days or ask you to pay another way.
I don't think they'll cut you off straight away, but they'll want you to sort it out. Are you in a contract? If so, they'll expect you to pay to the end of the contract whether you can afford it or not.
Is this a one off, or the start of a slippery slope into financial difficulties? Have you had any advice about getting out of overdraft, getting out of debt and making whatever changes will help with this?
As always, Moneysaving Expert will point you in the right direction, whether it's just a matter of rearranging your finances a little and setting a budget, or if more formal help is needed.
www.moneysavingexpert.com/loans/debt-help-plan/