Buying in app purcahses

1. You need a valid credit card link to your Apple ID.

2. Make sure in Settings > General > Restrictions: OFF > In-App Purchases : ON

i bought a game on my old apple id and when i got a new apple id i got it copied across and now i cant buy anthing on it. do i have to rebuy the app on my current I'd again and if so will i lose all my data? I don't want to start the game all over again. The app is clash of clans if that helps

Yes, you need to buy it again with the new Apple ID and yes, the data is also gone.

Content bought using one Apple ID cannot be merged or transferred to another Apple ID.