Thanks for reaching out to us on our Community Forums leruero, and a very warm welcome to you!
Sorry to hear of the confusion caused over the crediting value.
Looking at the image you've uploaded, towards the bottom, this does show the inclusion of a £75.00 credit.
Virgin Media will always issue their customer with a double bill for the first bill of a new connection, that shows is charged at £26.50 per month,
In this circumstance, the first bill would be a total of £53.00 for the services.
This would then leave £22.00 credit remaining from the original £75.00 figure to be taken from the following bill
Thanks,
David_Bn