Issues, Issues, Issues…
I used that app for 3 years. After upgrade fo IOS 15 the new version of app was released and since then I was unable to restore the purchase while activating my subscription. I was in touch with developers few times and provided full technicnal feedback including screenshots of error messages. The response was vague with final response that with IOS 15.2 all is now fine, which wasn’t. I ended with subscription valid till December 2022 without being able to use it. After a while the developers stopped to respond to my emails. What a pity.