When someone calls me and I wasn't able to pick up the phone, their call
doesn't go directly on my voicemail. After the rings, the other party would
then hear busy signal. Is there a problem with the phone?
Sounds more like an issue with your carrier and not the phone. Voicemail may also not be set up properly either... Try accessing it from your phone to make sure all the settings are correct first. If it seems to be okay, call your provider and have them check into it.
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