Business - Payments - In-App Purchase

Hello, everyone. I'm using Bubble.io to develop a matching app for a transportation company and try to publish it to the App Store by using BDK plugin. The URL of the matching app is as follows https://carrier-s.com I received the following message from the App Store, and I'm not sure what to do. The いいね can be purchased in the app using payment mechanisms other than in-app purchase. If anyone knows anything about in-app purchases, please let me know. Currently, payments are made via Stripe.