Why when calling our Japanese customers from Zendesk Talk is the Caller ID is Unknown/Blocked/Withheld?
Unfortunately, some Japanese carriers refuse to honour caller ID from international carriers when the caller ID is a Japanese number. Numbers beginning with +81 3XXXXXXX have been identified as having this issue.
Our provider have provisioned KDDI numbers which preserve the caller ID. To resolve the problem you should select a number beginning with +81 5XXXXXXX.
Please reach out to us if you have further questions.