Can my employer deny my FMLA in NJ?

Can I inquire about the circumstances under which my employer in New Jersey may deny my request for Family and Medical Leave Act (FMLA) leave? I understand that FMLA provides eligible employees with job-protected leave for specified family and medical reasons, but I'm unsure if there are any situations where my request could be denied. Could you elaborate on the potential reasons for an employer to decline an FMLA request in New Jersey?