There are many tools available online to remove duplicate contacts from a VCF file, but I recently used the
MacSonik VCF Duplicate Remover. This utility can separate and remove duplicate contacts from a VCF file in bulk. Additionally, the utility offers two ways to name contacts in VCF files: you can save contacts based on First Name, Last Name, Mobile Number, and Email, or you can save them using the vCard file name.