You can see in error in events :
Tue Sep 21 23:26:37 2021 -> ClamAV update process started at Tue Sep 21 23:26:37 2021Tue Sep 21 23:26:37 2021 -> ^DNS Update Info disabled. Falling back to HTTP mode.Tue Sep 21 23:26:37 2021 -> ^FreshClam previously received error code 429 from the ClamAV Content Delivery Network (CDN).Tue Sep 21 23:26:37 2021 -> This means that you have been rate limited by the CDN.Tue Sep 21 23:26:37 2021 -> 1. Run FreshClam no more than once an hour to check for updates.Tue Sep 21 23:26:37 2021 -> FreshClam should check DNS first to see if an update is needed.Tue Sep 21 23:26:37 2021 -> 2. If you have more than 10 hosts on your network attempting to download,Tue Sep 21 23:26:37 2021 -> it is recommended that you set up a private mirror on your network usingTue Sep 21 23:26:37 2021 -> cvdupdate (https://pypi.org/project/cvdupdate/) to save bandwidth on theTue Sep 21 23:26:37 2021 -> CDN and your own network.Tue Sep 21 23:26:37 2021 -> 3. Please do not open a ticket asking for an exemption from the rate limit,Tue Sep 21 23:26:37 2021 -> it will not be granted.Tue Sep 21 23:26:37 2021 -> ^You are still on cool-down until after: 2021-09-22 00:29:41
it means that ClamAV repositories servers are more sensible and make the updates sometimes take too long time to be updated.
To fix this issue, Artica Tech as build it's own ClamAV repository, for versions before 4.30x Service Pack 331, you need to apply this HotFix:
http://articatech.net/download/wiki/4.30/ntpdate/artica-4.30.000000.tgz
It can be applied only for all versions before 4.30x Service Pack 331 using the same method to apply a Service Pack
The difference is when you will apply the Hotfix, Artica claim that the version is the same.
Did not care about the error, the HotFix will be correctly applied.