Issues with Testing Promotional Offers for Auto-Renewable Subscriptions (StoreKit 2)

We are in the process of implementing promotional offers for auto-renewable subscriptions in our app using StoreKit 2.

For testing, we use a sandbox user alongside a new user on our platform. I can successfully purchase an Introductory Offer through the app. Once the user is eligible for a Promotional Offer (based on a previous purchase), we retrieve the Promotional Offer identifier and signature from our backend and display the offer.

After initiating the purchase and having the user enter their Sandbox password, the transaction is added to the Payment Queue. However, it fails with the following error:

Purchase failed error: invalidOfferSignature

Additionally, the error returned is:

"Purchase did not return a transaction: Error Domain=ASDServerErrorDomain Code=3903 "Unable to Purchase" UserInfo={NSLocalizedFailureReason=Unable to Purchase, client-environment-type=Sandbox, AMSServerErrorCode=3903, storefront-country-code=IND}"

We are using StoreKit 2 APIs for this process.

Has anyone encountered this issue when working with StoreKit 2, or found a solution to resolve it?

Issues with Testing Promotional Offers for Auto-Renewable Subscriptions (StoreKit 2)
 
 
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