Sorry to hear about trouble with voicemails not being deleted properly in the mailbox. I know how important it is that people can leave you messages, so I really want to get this fixed for you. There are a number of things that could cause this. When you activated your new phone, did you do so with a SIM card that was in a non-iphone previously? If so, your cell phone may be out of sync with the voicemail system, as iPhones use a different mailbox setup from other phones. Do you have your phone's cellular data turned on? Keep us posted and we'll go from there.
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