In app purchase for storage subscription with no duration

I need to implement storage subscription in my iOS app with in-app purchase. But unlike renewable or non-renewing subscriptions, I do not want to add a time constraint for storage. The user can use the purchased storage for any time duration, and it will not automatically renewed.

What is the type of the in‑app purchases that I should use for this?
In app purchase for storage subscription with no duration
 
 
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