Siri not connecting to mobile data on IPhone13 v15.2

iOS and iPadOS

I just purchased iPhone 13 Pro with Telstra as my provider. Transferred previous SIM from SE 2020 to new phone. Seems most things work,except when I am out and about and ask Siri to open any of the 3rd party apps like Seeing AI or other navigation apps. The first time I ask, it says that it is having difficulty connecting, make sure your device is on the same wifi network as this Home Pod. Yes, it is saying I am using a home Pod.when I manually initiate an app when out and about, it works no problem. But the Siri thing is problematic. I don’t wish to stay on phone with Telstra or Apple Support if someone here might know what the setting change is that I need. Thanks