Internal transfer denied

I just finished my first year as a middle school ELA teacher, but my goal has always been to teach high school.

I interviewed at all three high schools in my district. One never responded, one principal wanted to hire me, but HR blocked the transfer, and the third rejected me after a second interview.

Is this normal? Do districts usually want teachers to get more experience before moving from middle school to high school, or is this a sign that HR doesn't view me favorably?

Honestly, this has been really discouraging.