Bug sometimes particlestrip and orient face camera position doesn't work together

unity version: 2021.3.6f1

sometimes it works but not always...I'm a bit confused. I've included both in the attached.
without facing camera:


with facing camera


see those white dots? it's the only stripe piece I can see.

And it's not a camera facing problem. I put the camera at (0,0,-10) and the test object was at (0,0,0)
And the current viewport (camera or whatever) was also very close to the scene camera

I've also attached my testing visual effect graph in the attachment area.

Please help! Thanks!!

 

sorry my fault.
used the wrong trigger....

it should be trigger over time...case closed