I went to the File Manager in Minehut then went to plugins then added your plugin... it says it might not be supported. And it doesn't work. Why?

Can you send me the console logs?

Server starting, setting up fifo connections and writing server ready.
Target java version specified (16).
OpenJDK 64-Bit Server VM warning: Option --illegal-access is deprecated and will be removed in a future release.
System Info: Java 16 (OpenJDK 64-Bit Server VM 16.0.1+9) Host: Linux 5.8.0-53-generic (amd64)
Loading libraries, please wait...
2021-09-23 01:06:38,460 main WARN Advanced terminal features are not available in this environment
[01:06:42 INFO]: Environment: authHost='https://authserver.mojang.com', accountsHost='https://api.mojang.com', sessionHost='https://sessionserver.mojang.com', servicesHost='https://api.minecraftservices.com', name='PROD'
[01:06:42 INFO]: Reloading ResourceManager: Default, bukkit
[01:06:43 INFO]: Loaded 7 recipes
[01:06:45 INFO]: Starting minecraft server version 1.17
[01:06:45 INFO]: Loading properties
[01:06:45 INFO]: This server is running Paper version git-Paper-63 (MC: 1.17) (Implementing API version 1.17-R0.1-SNAPSHOT) (Git: 1d194e5)
[01:06:45 INFO]: Debug logging is disabled
[01:06:45 INFO]: Server Ping Player Sample Count: 12
[01:06:45 INFO]: Using 4 threads for Netty based IO
[01:06:45 INFO]: Default game type: SURVIVAL
[01:06:45 INFO]: Generating keypair
[01:06:45 INFO]: Starting Minecraft server on *:25575
[01:06:45 INFO]: Using epoll channel type
[01:06:46 INFO]: [ViaVersion] Loading ViaVersion v4.0.1
[01:06:46 INFO]: [ViaVersion] ViaVersion 4.0.1 is now loaded, injecting!
[01:06:46 INFO]: [ViaVersion] Loading 1.12 -> 1.13 mappings...
[01:06:46 INFO]: [ViaVersion] Loading 1.13 -> 1.13.2 mappings...
[01:06:46 INFO]: [ViaVersion] Loading 1.13.2 -> 1.14 mappings...
[01:06:46 INFO]: [ViaVersion] Loading 1.14 -> 1.15 mappings...
[01:06:46 INFO]: [ViaVersion] Loading 1.15 -> 1.16 mappings...
[01:06:46 INFO]: [ViaVersion] Loading 1.16 -> 1.16.2 mappings...
[01:06:47 INFO]: [ViaVersion] Loading 1.16.2 -> 1.17 mappings...
[01:06:47 INFO]: Server permissions file permissions.yml is empty, ignoring it
[01:06:47 WARN]: **** SERVER IS RUNNING IN OFFLINE/INSECURE MODE!
[01:06:47 WARN]: The server will make no attempt to authenticate usernames. Beware.
[01:06:47 WARN]: Whilst this makes it possible to use BungeeCord, unless access to your server is properly restricted, it also opens up the ability for hackers to connect with any username they choose.
[01:06:47 WARN]: Please see http://www.spigotmc.org/wiki/firewall-guide/ for further information.
[01:06:47 WARN]: To change this, set "online-mode" to "true" in the server.properties file.
[01:06:47 INFO]: Preparing level "world"
[01:06:47 INFO]: -------- World Settings For [world] --------
[01:06:47 INFO]: Experience Merge Radius: 3.0
[01:06:47 INFO]: Cactus Growth Modifier: 100%
[01:06:47 INFO]: Cane Growth Modifier: 100%
[01:06:47 INFO]: Melon Growth Modifier: 100%
[01:06:47 INFO]: Mushroom Growth Modifier: 100%
[01:06:47 INFO]: Pumpkin Growth Modifier: 100%
[01:06:47 INFO]: Sapling Growth Modifier: 100%
[01:06:47 INFO]: Beetroot Growth Modifier: 100%
[01:06:47 INFO]: Carrot Growth Modifier: 100%
[01:06:47 INFO]: Potato Growth Modifier: 100%
[01:06:47 INFO]: Wheat Growth Modifier: 100%
[01:06:47 INFO]: NetherWart Growth Modifier: 100%
[01:06:47 INFO]: Vine Growth Modifier: 100%
[01:06:47 INFO]: Cocoa Growth Modifier: 100%
[01:06:47 INFO]: Bamboo Growth Modifier: 100%
[01:06:47 INFO]: SweetBerry Growth Modifier: 100%
[01:06:47 INFO]: Kelp Growth Modifier: 100%
[01:06:47 INFO]: Entity Activation Range: An 32 / Mo 32 / Ra 48 / Mi 16 / Tiv true
[01:06:47 INFO]: Hopper Transfer: 8 Hopper Check: 1 Hopper Amount: 1
[01:06:47 INFO]: Custom Map Seeds: Village: 10387312 Desert: 14357617 Igloo: 14357618 Jungle: 14357619 Swamp: 14357620 Monument: 10387313 Ocean: 14357621 Shipwreck: 165745295 End City: 10387313 Slime: 987234911 Bastion: 30084232 Fortress: 30084232 Mansion: 10387319 Fossil: 14357921 Portal: 34222645
[01:06:47 INFO]: Max TNT Explosions: 100
[01:06:47 INFO]: Tile Max Tick Time: 50ms Entity max Tick Time: 50ms
[01:06:47 INFO]: Entity Tracking Range: Pl 48 / An 48 / Mo 48 / Mi 32 / Other 64
[01:06:47 INFO]: Allow Zombie Pigmen to spawn from portal blocks: true
[01:06:47 INFO]: Item Merge Radius: 2.5
[01:06:47 INFO]: Item Despawn Rate: 6000
[01:06:47 INFO]: View Distance: 8
[01:06:47 INFO]: Arrow Despawn Rate: 1200 Trident Respawn Rate:1200
[01:06:47 INFO]: Zombie Aggressive Towards Villager: true
[01:06:47 INFO]: Nerfing mobs spawned from spawners: false
[01:06:47 INFO]: Mob Spawn Range: 6
[01:06:48 INFO]: -------- World Settings For [world_nether] --------
[01:06:48 INFO]: Experience Merge Radius: 3.0
[01:06:48 INFO]: Cactus Growth Modifier: 100%
[01:06:48 INFO]: Cane Growth Modifier: 100%
[01:06:48 INFO]: Melon Growth Modifier: 100%
[01:06:48 INFO]: Mushroom Growth Modifier: 100%
[01:06:48 INFO]: Pumpkin Growth Modifier: 100%
[01:06:48 INFO]: Sapling Growth Modifier: 100%
[01:06:48 INFO]: Beetroot Growth Modifier: 100%
[01:06:48 INFO]: Carrot Growth Modifier: 100%
[01:06:48 INFO]: Potato Growth Modifier: 100%
[01:06:48 INFO]: Wheat Growth Modifier: 100%
[01:06:48 INFO]: NetherWart Growth Modifier: 100%
[01:06:48 INFO]: Vine Growth Modifier: 100%
[01:06:48 INFO]: Cocoa Growth Modifier: 100%
[01:06:48 INFO]: Bamboo Growth Modifier: 100%
[01:06:48 INFO]: SweetBerry Growth Modifier: 100%
[01:06:48 INFO]: Kelp Growth Modifier: 100%
[01:06:48 INFO]: Entity Activation Range: An 32 / Mo 32 / Ra 48 / Mi 16 / Tiv true
[01:06:48 INFO]: Hopper Transfer: 8 Hopper Check: 1 Hopper Amount: 1
[01:06:48 INFO]: Custom Map Seeds: Village: 10387312 Desert: 14357617 Igloo: 14357618 Jungle: 14357619 Swamp: 14357620 Monument: 10387313 Ocean: 14357621 Shipwreck: 165745295 End City: 10387313 Slime: 987234911 Bastion: 30084232 Fortress: 30084232 Mansion: 10387319 Fossil: 14357921 Portal: 34222645
[01:06:48 INFO]: Max TNT Explosions: 100
[01:06:48 INFO]: Tile Max Tick Time: 50ms Entity max Tick Time: 50ms
[01:06:48 INFO]: Entity Tracking Range: Pl 48 / An 48 / Mo 48 / Mi 32 / Other 64
[01:06:48 INFO]: Allow Zombie Pigmen to spawn from portal blocks: true
[01:06:48 INFO]: Item Merge Radius: 2.5
[01:06:48 INFO]: Item Despawn Rate: 6000
[01:06:48 INFO]: View Distance: 8
[01:06:48 INFO]: Arrow Despawn Rate: 1200 Trident Respawn Rate:1200
[01:06:48 INFO]: Zombie Aggressive Towards Villager: true
[01:06:48 INFO]: Nerfing mobs spawned from spawners: false
[01:06:48 INFO]: Mob Spawn Range: 6
[01:06:48 INFO]: -------- World Settings For [world_the_end] --------
[01:06:48 INFO]: Experience Merge Radius: 3.0
[01:06:48 INFO]: Cactus Growth Modifier: 100%
[01:06:48 INFO]: Cane Growth Modifier: 100%
[01:06:48 INFO]: Melon Growth Modifier: 100%
[01:06:48 INFO]: Mushroom Growth Modifier: 100%
[01:06:48 INFO]: Pumpkin Growth Modifier: 100%
[01:06:48 INFO]: Sapling Growth Modifier: 100%
[01:06:48 INFO]: Beetroot Growth Modifier: 100%
[01:06:48 INFO]: Carrot Growth Modifier: 100%
[01:06:48 INFO]: Potato Growth Modifier: 100%
[01:06:48 INFO]: Wheat Growth Modifier: 100%
[01:06:48 INFO]: NetherWart Growth Modifier: 100%
[01:06:48 INFO]: Vine Growth Modifier: 100%
[01:06:48 INFO]: Cocoa Growth Modifier: 100%
[01:06:48 INFO]: Bamboo Growth Modifier: 100%
[01:06:48 INFO]: SweetBerry Growth Modifier: 100%
[01:06:48 INFO]: Kelp Growth Modifier: 100%
[01:06:48 INFO]: Entity Activation Range: An 32 / Mo 32 / Ra 48 / Mi 16 / Tiv true
[01:06:48 INFO]: Hopper Transfer: 8 Hopper Check: 1 Hopper Amount: 1
[01:06:48 INFO]: Custom Map Seeds: Village: 10387312 Desert: 14357617 Igloo: 14357618 Jungle: 14357619 Swamp: 14357620 Monument: 10387313 Ocean: 14357621 Shipwreck: 165745295 End City: 10387313 Slime: 987234911 Bastion: 30084232 Fortress: 30084232 Mansion: 10387319 Fossil: 14357921 Portal: 34222645
[01:06:48 INFO]: Max TNT Explosions: 100
[01:06:48 INFO]: Tile Max Tick Time: 50ms Entity max Tick Time: 50ms
[01:06:48 INFO]: Entity Tracking Range: Pl 48 / An 48 / Mo 48 / Mi 32 / Other 64
[01:06:48 INFO]: Allow Zombie Pigmen to spawn from portal blocks: true
[01:06:48 INFO]: Item Merge Radius: 2.5
[01:06:48 INFO]: Item Despawn Rate: 6000
[01:06:48 INFO]: View Distance: 8
[01:06:48 INFO]: Arrow Despawn Rate: 1200 Trident Respawn Rate:1200
[01:06:48 INFO]: Zombie Aggressive Towards Villager: true
[01:06:48 INFO]: Nerfing mobs spawned from spawners: false
[01:06:48 INFO]: Mob Spawn Range: 6
[01:06:48 INFO]: Preparing start region for dimension minecraft:overworld
[01:06:51 INFO]: [ViaVersion] Loading block connection mappings ...
[01:06:54 INFO]: Time elapsed: 5694 ms
[01:06:54 INFO]: Preparing start region for dimension minecraft:the_nether
[01:06:58 INFO]: Time elapsed: 4493 ms
[01:06:58 INFO]: Preparing start region for dimension minecraft:the_end
[01:07:02 INFO]: Preparing spawn area: 0%
[01:07:02 INFO]: Preparing spawn area: 0%
[01:07:02 INFO]: Preparing spawn area: 0%
[01:07:02 INFO]: Preparing spawn area: 0%
[01:07:02 INFO]: Preparing spawn area: 0%
[01:07:02 INFO]: Preparing spawn area: 0%
[01:07:02 INFO]: Preparing spawn area: 0%
[01:07:02 INFO]: Preparing spawn area: 0%
[01:07:02 INFO]: Preparing spawn area: 0%
[01:07:03 INFO]: Preparing spawn area: 0%
[01:07:03 INFO]: Time elapsed: 4551 ms
[01:07:03 INFO]: [ViaVersion] Enabling ViaVersion v4.0.1
[01:07:03 INFO]: Running delayed init tasks
[01:07:03 INFO]: [ViaVersion] ViaVersion detected server version: 1.17 (755)
[01:07:03 INFO]: [ViaVersion] Finished mapping loading, shutting down loader executor!
[01:07:03 INFO]: Done (18.157s)! For help, type "help"
[01:07:03 INFO]: Timings Reset

I added your plugin to a new server so this is the logs of me just booting it up

Do you want me to try to kill somone so you can see it?

rename it to just lifesteal-smp-plugin without the (1) maybe, idk