Sim Card

Have you checked to see whether the eSIM is active on your iPhone 13 Pro Max? If you have cellular service and have confirmed that there is no physical SIM card in your iPhone, then your cellular service provider may be providing service over an eSIM.

If you have no service and no physical SIM card, then contact your carrier to activate service on your iPhone.

Axel F.

Normally you transfer the sim card from your old iPhone to the new iPhone or request a new sim card from your service provider with you number and service plan.