My situation has been now resolved by TomTom Support.
I did test the GO620 as suggested earlier. When the results were the same after a week or so. I went back to TomTom Support and re-stated my case.
The significant part of their reply below was that they had to do something with my device. As soon as I turned it on after their email, it showed a very quick update service and then presented the camera updates and has been doing so consistently for the last two weeks (as it was before the issue).
The reply from TomTom was:
Thank you for taking the time to contact Tom Tom Customer Support. My name is XXXX and I am glad to assist you.
The reference number for your query is 190712-002315.
I understand from your e-mail that you are unable to get the speed camera updates on your Go 620 Wi-Fi.Please be assured that I will put my best efforts to assist you.
Apologies for the inconvenience caused to you.
While checking the details on your account, I am glad to confirm that the unlimited world maps and regional speed camera is active on your Go 620 Wi-Fi.
Due to some technical issue,the speed camera was not offered, however,I have done necessary changes on the device.
In order to refresh the services, please perform the below troubleshooting steps:-
Soft Reset :-
Press and hold the On/Off button until you hear the drum sounds and the device restarts. This can take 30 seconds or more.
Factory Reset :-
On the map or guidance view, select the Main Menu button .
Select Settings , then select System.
Select Reset three times to reset the factory settings.
When prompted to select a language, perform a soft reset of your navigation device.
Once done,please refer the below link to update your device using Wi-Fi :-
UPDATING YOUR DEVICE USING WI-FI®
I am sure the above given information is helpful to you. If you have any query or require further assistance, please feel free to get back to us anytime.
Thank you for your time and for giving me an opportunity to assist you.
With Kind Regards
Customer Service Representative
The TomTom Customer Care Team