I have verified that the Paid Apps Agreement, bank account details, tax forms, compliance and other related information are all valid. I created two IAP products using identical configurations. One can be purchased normally, while the other returns an invalid product error. Moreover, any newly created products still trigger the same invalid product error. I have attempted multiple troubleshooting steps: clearing purchase records for sandbox testers, creating new sandbox accounts, uninstalling the app, and restarting devices. Unfortunately, I have still not identified the root cause. I hope to receive additional troubleshooting guidance.

I finished filling in business information and configuring Xcode, then created the first IAP product, which functioned properly the following day. I created the second product afterwards. After a three-day waiting period, it still triggers an invalid product error. Any newly created products I added afterward also show invalid product errors. All product details are completed and marked Ready to Submit, but I still cannot figure out what causes this problem.