Default vCenter 9.0 evaluation License gets expired in 60 days. If the vCenter is not Licensed using VCF Operations within this 60 days, VCF Operations won't be able to proceed the installation and import vCenter.
Obtain the VMware Cloud Foundation Operations 9.x OVA file from the Broadcom Support Portal and deploy the it directly to one of the ESXi Hosts and configure License.
Note: If the ESXi Host License is also expired, you may need to re-install one of the Hosts in the environment to deploy the VMware Cloud Foundation Operations 9.x OVA and power it on.