Firework dispenser firing once

I'm playing in a realm with only two people, and I've tried creating a firework dispenser, but it only fires once. I place down the dispenser, filled it with 6 identical rockets to test it, and when I flip the switch, it works exactly once, leaving the remaining 5 rockets untouched. It will only work again if i destroy the dispenser and replace it, which again, only works once.

 

The pre-made randomized fireworks don't work either. They launch, but never explode.