If you hear a coded error message, it is usually due to an internal error and it should be reported to our support team as soon as possible.
However, there are a couple of common ones that are encountered regularly:
503 - No Plan selected. 512 - The person you are calling has their VoIP phone switched off, or it is unreachable. 513 - Upstream carrier congestion (or disconnected phone number). 514 - The phone number you have dialed doesn't exist. 508 - [Anonymous SIP] If you get this error, your phone may not be authenticated with our servers.