not eligible for teaching area despite degree

hi yall potential pre-service teacher here. currently hold a bachelor of laws and a bachelor of politics and international relations. i have received an offer for master of teaching (secondary) from acu with a teaching area of legal studies but they ruled i'm not eligible for a politics. politics is a senior cert subject in my local jurisdiction (an aspect of eligibility mentioned by the uni).

is there any reason i might not be aware of that this would happen that isn't just a faculty mistake? not keen on making a big deal out of it just yet but would be a bit sad if i can't teach from both my quals.