Direct Debit £50 top-up

I accidentally pressed the Direct Debit Top Up of £50.00 and it is now pending, does this come out with my direct debit next month? or does this payment automatically come out?

Not use to the whole bulb layout and paying before you use instead of paying after you receive your statement, its all weird for me!

Thanks,

Why weird? If for example you go to the cinema do you pay before or after seeing the film?

If you pressed the top up button and it now shows as pending it will be taken in the next couple of days and not at the same time as the normal dd payment.