Finally received a reply from Virgin about my missing rewards :
Thanks for your email to Virgin Media about your Crave upgrade allowance.
We're concerned to hear that your upgrade allowance is not longer viewable, we can certainly understand how frustrating this can be.
We can confirm that we're currently experiencing an IT issue with some customers accounts no longer showing how much Crave allowance they have.
We're currently aware of this and our IT department is working on the issue as we speak.
While we currently do not have a timescale for the resolution, we confident that everything will be as it should be in no time at all.
Thanks for taking the time to write to us.
My account still shows nothing even though I know there is at least £20 there. I just hope it shows back again soon