24v motor installed on Rega Planar3 and platter won't spin

My Rega Planar 3 works perfect before I change motor with 24v upgrade kit.
After I change, pulley spins and subplatter spins but
when i put on my glass platter, the glass platter won't spin.
Motor and pulley are installed in center position.
Now sure why?
I didn't took off subplatter while i am installing, so it's not subplatter.
What is possible cause?