I moved my phone and internet from Optus to TPG. This included porting my Optus phone number. According to TPG this process was completed on 1st May 2020.
When using the home phone, I am able to make outgoing phone calls. When calling another phone, it correctly displays my home number as the caller ID.
When I call my home phone from an Optus mobile I am unable to connect. A message is played saying the number is disconnected. I can successfully call the home phone using Skype. A TPG tech support person was able to call my home phone. Other Optus customers who have tried to call have said they get the message about the number being disconnected.
I am continually transferred from Customer Service to Tech Support and back.
There appears to be lots of similar questions on these TPG forums