Migration is a powerfull feature allowing ISP/Reseller to create Users Data on Bulk Upload.
Before starting migration:
The Corresponding Bill Plan, IP Pools, Location &Sub Location must exists, if not, it must be created in neuCRM.
Please note that you need to enter SubPlan ID (Nemerical value) not the Plan ID in the Uploading Template file. If given SubPlan ID or IP Pool Name or Location not exists in neuCRM, neuCRM will identify the missing thing and alerts you during Validation step.
Don't worry, you are not allowed to continue the migration until you are clearing the all errors.