I have to pay for an album I synced?

I have tried to sync a CD on my laptop on iTunes to my iPod, normally it works but this time when I go on my Albums on my iPod and click on that album it says I have to pay 99p for each song but I don't wan to pay for an album I've already payed for. This is the first time this has happened:(

Would be great if someone could help? Thanks:)