Hi A_Undre21,
The forum shows that you have just joined, so welcome to VM.
If you've just joined then it's likely that this your first bill. When joining you are generally allocated a billing date. The first bill will include the charges you've incured from the date of the services being activated until the end of the current billing period, and will also include a months payment in advance.
The following page explains your first bill:-
https://www.virginmedia.com/help/virgin-media-first-bill
Some people pay their first bill over the phone or internet, however if you have set up a direct debit, then the direct debit payment will still be taken, so it will appear that you've been charged twice. If that's the case then your next bill will include a credit for the additional payment that you made.