We'd be more than happy to provide you with some more details about setting up your voicemail after changing your SIM card. If you have a new phone, or recently changed your phone or SIM card, you may need to Set Up Your Voicemail. Visit Device Support to learn how to set up voicemail on your phone. Ensure you set up your voicemail within 60 days of activation or it’ll be automatically removed from your account. Let us know if you have any further questions or concerns.
Sean, AT&T Community Specialist
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