Following these steps will allow your environment to be provisioned on time:

Step 1 - Performing the initial login, following the instructions provided in the provisioning e-mail, within 30 days of receipt, will trigger the provisioning of your system.
Step 2 - Once you have logged on for the first time using SAP for Me (me.sap.com), as a super administrator you can create additional S-users by following these instructions.
Step 3 - Create access for an S-user in the SAP Commerce Cloud Portal by following these instructions.
Step 4 - By default, you are entitled to two tenants (1 Small Sandbox and 1 Production). The first tenant (1 Small Sandbox) is provisioned by SAP. Discuss with your implementation partner when to provision the other tenant(s). You can find all the instructions on how to provision tenants here: Using SAP for Me to Provision Environments | SAP Help Portal. The total number of tenants depends on your contract. For further information about all different SAP Commerce editions, please check here: Commerce Entitlement Guide.pdf.