If you have spoken to support and they have sent you a replacement SIM card then it will be already linked to your existing number so will just need the support team to activate it for you.
If you are currently with Boost and have purchased a sim pack as these already have a number allocated they are typically not able to be used for an existing number on the same network. The support team by phone will be your best bet to discuss.
If you have purchased a sim pack and are bringing a number from another carrier you can activate it online or with the support of the accounts team by phone.
Unfortunately we can't access account details on the Community, for SIM enquires, please contact Boost on 125 8881(8am - 9pm) or via Live Chat Get Help which is available 24 x7
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