WhatsApp On Symbian? Fix 2018 (Nokia E72)

Set the phone date to any date before June 30, 2017 like June 15, 2017. But not too old, preferably not before May 2017. Make sure that the “Automatic time and date” option in the phone is set to “Off” under Time and date settings. If this option is “On” – the date and time will automatically set to current by mobile network.
Now close WhatsApp completely (simply exiting it will not work as WhatsApp continues to run in the background). To force close WhatsApp completely you can use WhatsApp modifier app or you can simply switch off and then restart the phone as it will also close and relaunch WhatsApp.
WhatsApp will be fully functional again as it was running before July 18, 2017. Now you can send or receive messages as usual.