So far here's the only proven working method.
At the phone (smartphone), briefly enable "Aeroplane" mode and disable "Aeroplane" mode. Enable back the "hotspot" mode and connect to the hotspot to join the Cisco Webex meeting. For those who don't know about Aeroplane mode, it is a setting on smartphones (android / iPhone) to turn off all communication channels on the phone (wifi, cellular) originally meant for setting the phone during airplane take off to avoid interference with the electronics on aeroplane.
Do note that this method also solves and issue where you are not able to join into Cisco webex meetings when the Internet connection is good. Sometimes when I try to connect to Cisco webex meetings I will be getting a forever loading status and only way was to do the "Aeroplance" mode toggle method.
My tech guy's theory is Maxis Mobile networks has got some sort of security device to discourage people from using Maxis line as a hotspot to share data with other devices and people. Toggling the phone's "Aeroplane" mode will force the phone to refresh the network configuration with Maxis (eg change IP address).
The problem doesn't seem to occur on other networks (eg Celcom, Umobile, TM).
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