Missing info in rubric

Just venting and I already emailed my professor about this. Emailed Professor 1/8 with a question about what format to use for assignments and discussions as nothing was listed in rubrics or directions so I guessed when I received no response. Yet Professor replies to my discussion post telling me to use APA format and 2 references. I looked everywhere before I emailed him and he never responded and nothing is listed anywhere about what format or how many references. So how the heck would I know that if you don’t put it in the directions or rubric anywhere. I checked again after the reply and nothing. So I emailed him again pointing out THAT NOTING IS NOTED ANYWHERE. If I lose points over this I am going to fight it. I took screenshots of it too. Plenty of others used 0 references OR just 1 reference. How would people know what format or references to use if it isn’t posted anywhere?