What do you see now on the app?
1- If you see the paid emojis (Halloween button for example), the payment didn't succeeded. That can happens because many reasons: internet connections, apple payment process error... Try again, you will not be charged again if finally the payment worked.
2- If you don't see the buttons and after scrolling you don't see the new emojis, try to go to Settings (upper left button) and tap restore purchases. After that restart the app. If you still don't see it, try to delete and download again the app. That happens sometimes dure to server systems.
If that didn't solve the issue, It's a particular problem and we'll need to review manually.