You are unable to call an International Number, getting an error message "Your call cannot be completed at this time in the country you are trying. Please call later."
- Screenconnect access
- Hepic access
- TCPdump/Wireshark to collect/review SIP messages
- Knowledge of protocols and how to read and analyze SIP flow messages
One of the known causes behind the issue is that the number called is not a valid number or the issue with the end carrier. Before opening a support ticket, make sure to verify this by calling over another carrier and making sure the call goes through. If you cannot make a successful call this way, confirm the number and reach out to the end carrier so they can check their configuration for the number.
If you are able to make successful calls via another carrier, but the issue persists when calling through Kandy, we will need fresh call samples to start troubleshooting. Reproduce the issue and open a ticket with Support, making sure to describe the issue and any symptoms you observe, and add at least two call samples in the following format:
- Calling From Number:
- Calling To Number:
- Date of call: dd/mm/yy
- Time of call: xx:xx am/pm (time zone)
- Trouble observed: Inbound or Outbound
- Description of the failing scenario
First, ensure that the customer performed the recommended tests (calling from a different network/carrier), the number is valid, and that the issue is isolated only to calling with us.
Once you have the details and call samples from the customer, proceed with the steps below.
- In a Screenconnect VM use Hepic to search for the samples provided.
- If you see any failures in SIP signaling, see where these come from (our SBC, AT&T, customer side) and reach out to the SaaS, AT&T, or the customer with the findings. If no failures are found, open a ticket with AT&T to verify what they are seeing on their end.
Error Code 603 in SIP Trace
In one of the cases, the root cause identified from the SIP trace was error 603:
Error SIP 603 is usually returned as a response when the called party was successfully contacted but can not or does not wish to participate. So the next steps is to find out who returned the error to contact them.
Verify the IP with https://iplocation.io/
In the example above, the IP belongs to AT&T, so the ticket should be open with them. Further steps depend on the escalation feedback.
The issue was with the end carrier that fixed it after the customer reached out to them.
The Support Team will investigate and take appropriate actions. If needed, we may reach out to you to run certain checks or to reach out to third-party providers.
To verify that the issue is resolved, try to reproduce the failing scenario and see if a call is connected without issues.