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
Linked issues
Attachments
Comments 7

Thank you for your report!
We're tracking this issue in MCPE-118539, so this ticket is being resolved and linked as a duplicate.
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Thank you for your report!
We're tracking this issue in MCPE-118539, so this ticket is being resolved and linked as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
If you haven't already, you might like to make use of the search feature to see if the issue has already been mentioned.
Quick Links:
📓 Bug Tracker Guidelines – 💬 Community Support – 📧 Mojang Support
📓 Project Summary – ✍️ Feedback and Suggestions – 📖 Game Wiki