How to get the Fitness app back on my iPad

I subscribe to Fitness + and previously used it on my iPad for the bigger screen. The app has seemingly gone from my Home Screen and App Library. The app is not hidden in my App Library. When I search for it in the App Store I find it and it says ‘Open’ instead of ‘Get’ or the re-download symbol. When I hit open the app does seem to open but as soon as I enter another app it disappears. It can no longer be seen in multitasking view and the app is not on the Home Screen. Obviously I can search for it in the App Store if I want to use it but this is more annoying than having the app on the Home Screen.