hello.
on my app i have 3 different subscriptions of 1,3,12 months, i have to test it and something is going wrong.
i do all in this way
open the app
purchase 1 month subscription
close the app and under Settings->App Store->sandbox account->manage->subscriptions switch to 3 months subscription
after 5 minutes open up the app again and check that the current subscription is the 3 months one.
the downgrade it back to the 1 month one and a message that says "you have already purchased this item" will be showed.
are this ok? by the way my app is made with unity and their IAP, but the error is coming from IOS UI so should be related to the sandbox test part instead a problem with unity IAP..