I may be mistaken, but this might be intended. In the Java edition (I know, they're two completely separate versions) only naturally-spawning Drowned will drop items.
Sounds like an issue with your installation of Minecraft Bedrock Edition. If it's not occurring for your friends on the same server that you're having issues with, try uninstalling Minecraft Bedrock Edition and then reinstall it.
Jonah Long
I may be mistaken, but this might be intended. In the Java edition (I know, they're two completely separate versions) only naturally-spawning Drowned will drop items.