Fafsa with parents of A2 visa. 20-21

I am a US citizen, my parents are not diplomats but they do have A2 visas. maybe “foreign officials” is a little contradictory but My father is a local staff member of a foreign embassy and my mother just has the A2 visa but is not employed by the embassy. but legally I am a US citizen . The only issue I have is that my parents are tax-exempt and im not sure how to communicate that onto my FAFSA.