I’m new here btw😭😭

In the film, Tree seemed to be the only one to know that she was in a time loop; and no one else had a clue. (Although, in the first few minutes of Happy Death Day 2. Ryan was aware that he was in a time loop.) Tree also seemed to be the only one whose memory hadn't been wiped by the time loop; so why was Tree the only one to know that she was in a time loop?

As far as they know, There is not yet confirmed for Happy death day 3 , the first film came out for 2017 then A second film came out for 2019 which is the film series so there is not yet for Happy death day 3.