The trident doesn't appear in the player's hand, instead it shows at the neck or chest of the player. It is visible in first person and third person front. I have a few addons on my world so I tried it on another world and the results were same
Steps to Reproduce
1. Take a riptide trident
2. Use it a couple times until you don't see the trident in your hand. OR Sometimes it can happen just by holding it in the hand