Retrieving user apple ids from App store connect

Hi!
I have 2 apps in the app store, one for free (lite version) and one that costs money(premium version).

I am now developing an app with in app purchases that will replace those two.

The question is: How do I retrieve the users that already paid for the first app so they don't have to pay again?

Disclaimer: No, I don't have a separate database of those users.

Thanks in advance!
Retrieving user apple ids from App store connect
 
 
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