Not connecting to network in australia

[PaulSim_1818669]

My phone hasn’t connected to any network in Australia. My settings are as advised in the travelling abroad advice and I have tried resetting my phone. Any suggestions as to what I can try to get it to connect. It’s an iphone15. 
Thanks

[MSF]

@PaulSim_1818669 There seems to be an issue with Australia not allowing a phone to connect if it does not comply with VoLTE standards.