From the UI (Administrator --> Infrastructure) create an infrastructure with the following inputs:
VPC CIDR: 10.221.0.0/16
Subnet CIDR Mask 24
Availability Zones 2
This takes about 20 minutes. Kubernetes is the part that takes 15 minutes. Wait for the status to be completed. At the end of it, double check that a "plan" (Administrators--> Plans) has been created with the same name (non-prod).
If it has been more than 20 minutes then click on Faults (Administrator-->Faults) to see if there is an obvious error and if help is needed ping in the DuploCloud slack or teams channel.