Make sure you're doing the following

• You're using the latest build for your server version
• This isn't an issue caused by another plugin
• You've checked for duplicate issues
• You didn't use /reload

Describe the question
I want to make entity's invisible for some players but when i try to make them visible again i receive this error:

.... [19:55:36 WARN]: [ProtocolLib] [PacketFilterManager] [Core] Unsupported server packet in current Minecraft version: UPDATE_ENTITY_NBT[PLAY, SERVER, 253, classNames: [net.minecraft.server.v1_15_R1.PacketPlayOutUpdateEntityNBT] (unregistered)]
.... [19:55:36 WARN]: [ProtocolLib] [PacketFilterManager] [Core] Unsupported server packet in current Minecraft version: UPDATE_ENTITY_NBT[PLAY, SERVER, 253, classNames: [net.minecraft.server.v1_15_R1.PacketPlayOutUpdateEntityNBT] (unregistered)]

API method(s) used
I used the EntityHider class

Expected behavior
The Entity's will become visible again

Code
https://gist.github.com/dmulloy2/5526f5bf906c064c255e <- Entity Hider Class i used

                            EntityHider entityHider = new EntityHider(this, EntityHider.Policy.BLACKLIST);
                            for (Husk h1 : husks) {
                                if (!h1.equals(riders.get(p))) {
                                    entityHider.toggleEntity(p, h1);
                                }
                            }

Additional context
I can make the husks invisible but not visible again