Malfunction
This app is not behaving properly. It kept requesting the user to purchase the app. This is done in Chinese and points towards a Chinese site. BUT I have already purchased this app via Apple App Store. And have used it for a number years. It may be relevant that I have just updated to iPadOS 17.4.1 and this is the first time I use this app after the updating. The same malfunction is also encountered in my iPhone Pro Max that was updated to iOS 17.4.1