@Phillip_Bang, i have exactly the same problem. Good that I have found someone who also has the problem. I thought it was just me.
I have already made a post about this in the forum a little further up, but no one at MS seems to be taking an interest in it.
Due to this problem the state of the whole system is unusable at the moment.
After finally getting the JIT registration up and running, I am now running into the problem of Company devices not being cleanly separated from BYOD when logging in with the same account.
This is a reproducible error that simply must not exist!
At the moment, it's either or. Either no MAM policies and company devices as well as BYOD are allowed to do everything.
Or MAM policies and company devices as well as BYOD do something in between, that goes and that doesn't go.
Shame on Microsoft for completely dismantling a working process with something "better new".