Upvote:8
Schengen Flight Reservation Visa provides real flight reservations for visa application purposes, but according to their FAQs,
Our all provided itineraries are valid for up to 72 hours to up to 2 weeks time duration.
In particular, you will not be able to travel using this reservation. The 40 pounds you paid are not "part of the price of the ticket", it's just the fee that the website charges for this service. You can't get this money back or apply it toward the cost of the actual ticket.
Typically, the country you are travelling to will not require you to travel on the exact same flights you indicated when applying for the visa, so you are now free to book any flights you like on any airline, for example using a search engine like Google Flights.
If you want to avoid paying for such a service in the future, there are some options: