You can activate your new SIM card or eSIM yourself on the My Account Portal.
You can read more about eSIMs here.
Once logged in, navigate to Asset Management and select Activate/Disconnect Mobiles.
This page displays all SIM cards awaiting activation. If your mobile number is not displayed on this page, you will need to go to Mobile Management to activate your SIM.
Find the SIM you wish to activate, then click Activate.
Please be advised, this process can take up to twenty four hours to complete the changes with the network.