Without knowing your personal situation I can only suggest other family members, friends, neighbours, colleagues as a starting point.
Have you had a chance to look at our Network Status page for any outages that may be affecting your services? All you need to do is click the Mobile outages tab and search your address and you will see any outages reported.
If there are no outages in your area, you may need to perform a Network Reset on your phone. This will delete all saved network settings and WiFi passwords. This is to refresh all your Network settings on your phone without losing any data.
To do this, please follow the steps below:
iPhone - Tap Settings > General > Reset > Reset Network Settings
Samsung - Settings > General Management > Reset > Reset Network Settings
You may also find these troubleshooting steps useful for fixing mobile issues.
Is it possible to borrow a spare phone from a friend or family member to eliminate the issues being related to your S20 handset?
If you’re not having any success with the above, I'd recommend messaging us via the My Optus app to have a chat to our technical support team and they can assist further.
Our Messaging team is available 24/7 and are ready to assist customers as quickly as possible.
If for some reason you’re unable to use the My Optus app, please send a private message to the official Optus Facebook page or Twitter page for further assistance.
If the issue still continues then you are best to raise it with our Technical Support team via the → messaging service to assist you further as we don`t have access to customers account on this public forum.