While deploying a virtual machine VMware Aria Automation template, an administrator encounters the following error:

Error: com.vmware.xenon.common.LocalizableValidationException: Unable to find a valid subnet for network *Network_External' of type 'EXISTING’ with constraints '[dcimetro, tier:!]’, reasons: [Network profile ’publicnet / Metro* was skipped because [Network [Network_External] allocation: cannot allocate a network with static IP ranges for profile ’publicnet / Metro’.)]

Where should the administrator start to troubleshoot?