The SBS On Demand app preferred iOS version is iOS 14 and higher, however, if your device is running iOS version 13, you can still access the SBS On Demand app, provided it has already been downloaded on the device.
To reinstall an older version of the app, visit the App store on your device. The app store appears as a white A icon on a blue background on your iOS device
In the app store, tap the small blue silhouette in the top right of the app store screen. This will bring up your account page.
Scroll down until you see 'SBS On Demand' - there will be a small image next to it that looks like a cloud with an arrow.
Tap to reinstall your supported app version.