@Gagan37 - Is the status currently Active, OR sas it been active within 90 days?
If so, then yes, you can do this yourself in your My Account (as others posted).
See "How To Change Your SIM Card" at the bottom of this Help Article: https://www.publicmobile.ca/en/on/get-help/articles/sim-swap-fraud
If you do not have access to My Account or have never created an account before (maybe the case if you activated your account instore...once upon a time), then click here to request a SIM Swap with the Public Mobile Customer Support Agents (CSA): Submit ticket for a SIM SWAP , you may also wish to have you My Account registered at the same time if needed.
If the old phone number account was closed (in nonpay for over 90 days) or ported it out to another provider, then you will need to start a new account and go through the SIM card activation process with a new SIM card.
