480
SIP
480 Temporarily Unavailable
The callee's end system was contacted successfully but the callee is currently unavailable. The client may retry after some time.
当您看到此代码时
When the user exists but is not currently reachable — phone is off, DND mode enabled, or all lines are busy.
如何修复
Try calling again later. Check if the callee has DND enabled or if their device is powered off. Configure voicemail for unavailable scenarios.
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