Receiving an automated message informing you that a person's phone is not accepting calls can be disconcerting. For one thing, it prevents you from even leaving a message. Another problem is that there may not be another way to get in touch with your contact in a quick and timely manner. There are several reasons why a person's phone might be unable to accept calls.
One reason the number may be unable to accept calls is an issue with the service. If the lines to the phone are down, for example, the number may be unable to receive calls until the problem is fixed. You may also get this message if the phone is out of its service area and the owner elected not to receive out-of-area calls.
Some carriers allow users to block certain numbers, so if your number was blocked, you may get this message. Don't be alarmed if you think someone has blocked your number -- she may have blocked most numbers while waiting on an important call. Some people also block calls or disconnect their phones when they're engaged in an activity that requires a high level of concentration.
The phone service provider may remove the person's ability to receive calls in some circumstances. For example, the carrier might revoke service if a user hasn't paid her phone bill. Even if the bill is paid, a user who has gone far over her minutes or used too much mobile Internet may be cut off until payment arrangements are made. The carrier may also cut service for a short period if the user reports that the phone was lost or stolen.
There aren't many options available to you when you hear that a person's phone can't receive calls. You can try to call again later or call from a different phone. You can send an email or a text message, or contact the person via social media. You cannot complete your call until the phone is turned back on, service is restored or the person revises her settings.