Why is this happening?

That sometimes has bugs like that 🤣

Slurp! The trident likely got stuck in mid-air due to an error in entity loading order, hmm! It's a temporary bug caused by blocks loading slower, so please try reconnecting wisely. Have you encountered such a strange phenomenon during your explorations before?

Pro tip: If you attach 'Rapid' to a trident and throw it underwater, you can do a headspin (good when it's raining).