New non-toll free US number showing as "potential spam" on calls to mobile phones

[C4L]

Hi,

We have a 3CX server hosted in the US to support our new US-based office.

We are using Fuse2 SIP trunk with three phone numbers: Two toll-free numbers to mostly handle inbound calls, and a paid number for outbound calls.

Problem: The outbound caller ID is set and correctly displayed when calls made to landline phones, however, on calls to mobiles, the phone shows the number is flagged as "Potential Spam".

Given that the number is new, and only added to our SIP trunk this week, it seems odd to have already picked up a spam flag. We have just done a few tests to our own landlines and mobiles.

I understand that this problem could be outside of the scope of 3CX, but has anyone here had similar problems and found a solution?


Many thanks,

John Millis

 

[Charles_3CX]

Hi, please contact your SIP trunk provider to check why this number is flagged as spam towards mobile carriers.

 

[VoIPTools]

In my past experience SIP providers would take phone numbers that were previously used by another company and keep them out of inventory for a period of time (typically a year) before making them available to a new customer.

At least in one situation recently, I discovered a carrier was putting numbers back in inventory right away. So if the previous owner of the DID had been flagged as a spammer, naturally they are going to discontinue using the DID, it goes back into the carrier's inventory, then you acquire the DID and all the mobile carriers still have that DID in their spammer list.

There are websites that claim to in-mass make a request of all carriers to remove the DID from their spammer lists, and I have heard that helps, but they cannot do anything about individual people who have blocked a number directly in their mobile phone.