Purchased a car from a dealership in NJ, 50 days later still no title and they're ignoring my calls.

Location: Massachusetts. I purchased a car in NJ from a dealership and paid a 5k down payment and the dealership set me up with bank financing for the remainder. The 30 day temp tags are of course expired, I'm making payments on something I can't drive or register. I'm at a loss I never expected to have an issue with a title from a dealership. Im paying rental fees I need a car, the one they sold me is a lawn ornament. What are my options going forward to resolve this?