Okay @SharonW_1372981, for this you'd need to sign-in to your SMARTY account online, or the app, and purchase an add-on.
Just a reminder, EU roaming is included when purchase a SMARTY plan, which would allow you to use your call, text and data (up to 12GB/month) allowances while you're roaming in Austria.
Good luck @SharonW_1372981.
