Phantom callers

[STI-David]

Client has dedicated hosted by 3CX, Yealink SBC sets.
One user is experiencing almost constant phantom callers over last 3 days.
They are calling his DID.

How do I fix this?
Thank you.

 

[Charles_3CX]

Regarding your question, and to clarify, are the callers calling a DID assigned an extesnion? If you run a call report, are the numbers the caller is calling from the same or different numbers?

 

[STI-David]

Yes, the DID is assigned to a specific extension.
All different numbers.

 

[Charles_3CX]

Then there is not much you can do on the 3CX side other than to block the number from the management console > Security > Blacklisted Numbers section.

You can add numbers in the section using area codes if these are the same.

For example, use 1777* to block numbers that start with 1777, or speak with your VoIP provider to see what options they have for you.

 

[STI-David]

That's an option, but impractical, as the numbers are random and it would stop valid callers from said area codes.

I will contact voip.ms and see what they can offer.
Will advise.

Am I the only one to have this issue?

 

[Gbot@Okam]

Hello,
May i suggest as a workaround to configure a Digital receptionist on the DDI, "press 1 to reach your correspondant".
Not very convenient, but can help !

 

[STI-David]

Thank you for the DR option.
I guess that's a last resort option, as the client prefers live answer on his line.
Incidentally, Voip.ms also suggested using an IVR also.

The question is, what's to stop this happening on the many other DID's the client has?
Thanks again.

 

[TheodorosG_3CX]

Is there any pattern on the incoming calls?

 

[STI-David]

It started on 02/21/2024 3:40:27 PM till 02/21/2024 7:38:05 PM, then on 02/22/2024 9:42:53 AM till 02/22/2024 6:27:59 PM. Random times, sometimes a few minutes apart, then 20 minutes or an hour, then back to a few minutes between.

Voip.ms are not able to provide any further info, other than the CLID, which could be spoofed.
It's upsetting that there's no way to stop this from happening.

 

[STI-David]

The only commonality is that they appear to be Canadian cellular numbers from various carriers across the country.
I used https://freecarrierlookup.com/ to check a sample few.

 

[TheodorosG_3CX]

Have you tried the suggestion from my colleague to blacklist numbers with wildcard?
Also this must be clarified with the provider to block those calls to the DID.

 

[STI-David]

Have you tried the suggestion from my colleague to blacklist numbers with wildcard?
Also this must be clarified with the provider to block those calls to the DID.

My customers has clients across US and Canada, therefore blacklisting valid area codes will not work in this case.