I have a new Samsung Galaxy A33 5G. My wife bought 2 of them in Malaysia.
When I put my TPG SIM in the phone I get a message "SIM 1 not provisioned".
When I look for "Network operators" I get the message "Error while searching for networks"
When I put my wife's Optus SIM in the phone everything works.
When I put my TPG SIM back into my old phone everything works.
The network mode is LTE/3G/2G (auto connect).
I seleted the Network mode 5G/LTE/3G/2G (auto connect).
When I scan for Network operators I get 3 available networks:
Virgin - Unable to connect. Try Later
Telstra Mobile - Your SIM card does not allow a connection to this network
Vodafone AU - Your SIM card does not allow a connection to this network
After more testing I have noticed that my old phone still accepts calls even though it has no SIM. I tried restarting and a power off, but it still rings when called.
IGNORE THE ABOVE!!! 
My J7 has the capability for 2 SIM's and I was using the dead overseas SIM, not realising it was there.
So my TPG SIM was still in the phone - hence it would ring, and the old SIM would not work in the A33.
It is all working now. 
