Ads or paid users
This app is now deleted, and my subscription canceled. Thankfully Apple’s calculator app now has a built in currency converter. Greed killed this one.
Response from developer
This issue could have happened if you changed your iPhone or reinstalled the app. When you switch devices or reinstall, premium features often don’t automatically restore, and you may need to manually restore your purchase through Settings > Premium > Restore. It’s an unfortunate situation, especially given the timing and context you described. Hopefully, future interactions with other apps will be smoother.