Can you please send me a private message with your TPG account number and callback details? I'll have a tech specialist to ring you for further troubleshooting.
Was this resolved?
I've been having the same issue for a number of weeks now.
5G connection is fine, but then after a while, reverts to 4G connection & requires a restart in order to get the 5G connection again.
I've also tried the router in different positions, but the same thing seems to happen regardless.