Welcome to the Zwift Forums! I am Nelson from Zwift Support.
Thank you for the detailed description. If you haven’t already, can you try resetting your game preferences? Forgetting preferences and known devices will refresh the relationship between Zwift and the devices that can pair to Zwift.
To do so, please uninstall the Zwift app from your iPad device and then reinstall the app after downloading it from the App Store.
Please also ensure your smart trainer is not paired with other devices or apps at the same time. On the other hand, ensure you are logging out properly from the game after each Zwift session.
Please feel free to contact us if you need any further assistance after the steps above.