NBN, HFC, Huawei HG659, 100 Mbps, all working fine, except ...
We cannot call my wife's father in Queensland from the landline, but we can call her aunt, also in Queensland.
Calling 07 4992 8*** (father in Biloela) consistently gets the message: "The number you have called is not available from this service."
Calling 07 4974 1*** (aunt in Calliope) always goes straight through.
Calling father on the mobile (also TPG account) works OK.
Why can't we call and what do we need to do to get it to work?