web filtering service problem

We have an issue with web filtering service on XG .

All of a sudden , actually most probably starting from January 4th , the web filtering service does not work anymore .

Users can access any site , including the one that should not be allowed to them , and also the last logged entry is 4th January

We tried to restart the web filter service but nothing changed

What can be the issue , and how can we solve it ?

Do we have to reboot the firewall itself ?

thanks