I believe you want to use the IAP object, which is only available in licensed versions of Construct 2. It will save the purchase to the user's account, rather than the device. https://www.scirra.com/manual/173/iap
Currently the IAP plugin supports these platforms:
PhoneGap Build (iOS + Android)
CocoonJS (iOS + Android)
Ejecta (iOS)
Windows Store (Windows 8+, Windows Phone 8.1+)
Blackberry 10
Amazon Appstore
Tizen