Refusal to provide documentation for title and registration

I purchased used care from Carvana in April. Carvana provided temporary plates and said they would submit title and documentation to DMV and registration and permanent plates would be mailed within 6-8 weeks. They have since sent multiple temporary tags — all from different states — and now that the latest tags have expired they have said they can do nothing more. They cannot provide additional temporary tags and do not have the documentation for the permanent tags. When I complained they offered to give me $500 or help me buy a new car. Provide a title and any other necessary paperwork to allow me to register my car. And in the meantime, provide legitimate valid temporary plates while I wait for permanent plates.