Q: Clash of Clans-Lost village

Hi hrca97,

If I understand you are having trouble with an in-app purchase on your new iPhone 6s.  

I forgot to transfer old account

Do you mean that you are using a different Apple ID?   Updates and in-app purchases are tied to the original Apple ID that was used to purchase the app.   So, you would either have to sign out of the iTunes Store and sign in with your other Apple ID to download your past purchases, or edit your previous Apple ID email address.   I'll include some links below that will explain this in more detail.

Sign in with a different Apple ID on your iPhone, iPad, or iPod touch

Your Apple ID is the account you use to access Apple services like the App Store, Apple Music, iCloud, iMessage, FaceTime and more. It includes the email address and password you use to sign in as well as all the contact, payment, and security details you'll use across Apple services. You can sign in to all Apple services with a single Apple ID and password. 

If you're no longer using the email address associated with your Apple ID, you can change the email address that you use as your Apple ID, then use the steps below to update it in the services on your device.

If an app you installed unexpectedly quits, stops responding, or won’t open

Contact the app developer

1. Find the app in the App Store.
2. Tap the app, then tap Reviews.
3. Underneath App Store Customer Reviews, tap App Support. 
   
   
   
   
   
    

Take care,