Receipt verification in Sandbox for auto-renewal subscription items returns the same receipt each time and does not auto-renew.
(It's set to a monthly plan, so in a Sandbox environment, it should be an automatic update every 5 minutes)
Please let me know if there are any points to be aware of.
[Development environment]
Client: flutter
The in_app_purchase package is used to process the billing.
Server: JAVA
Make a receipt verification request to the Sandbox environment with the receipt sent by the client for the initial item purchase and the shared secret.