There are numerous ways to get around check-in failures with a Samsung/Android phone, depending upon the model and the most recent update you’ve made.
The most common reason is that Samsung devices select default apps automatically, making the browser the default way to open a Service Australia link instead of using the app.
Troubleshooting Step 1
Open the Settings app
Scroll down and tap on Apps.
Tap on Opening Links.
Select “open links in apps”
Troubleshooting Step Two
If Step 1 doesn't work, another solution is:
1. In settings search for "default app selection"
2. Change this from "set default apps automatically" to "ask before setting default apps"