Plugin Loading Error

[jaekwon-park]

Describe the bug
Mindustry 7.0 Essenstial plugin Load Error

To Reproduce
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2. Click on '....'
3. Scroll down to '....'
4. See error

Expected behavior
A clear and concise description of what you expected to happen.

Screenshots
[06-29-2021 16:16:30] [I] Plugin language: English
[06-29-2021 16:16:30] [E] Failed to load mod file config/mods/Essentials.jar. Skipping.
[06-29-2021 16:16:30] [E] java.lang.reflect.InvocationTargetException
at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:78)
at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:499)
at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:480)
at mindustry.mod.Mods.loadMod(Mods.java:788)
at mindustry.mod.Mods.loadMod(Mods.java:701)
at mindustry.mod.Mods.load(Mods.java:355)
at mindustry.Vars.init(Vars.java:308)
at mindustry.server.ServerLauncher.init(ServerLauncher.java:47)
at arc.backend.headless.HeadlessApplication.mainLoop(HeadlessApplication.java:66)
at arc.backend.headless.HeadlessApplication$1.run(HeadlessApplication.java:54)
Caused by: java.lang.NoSuchFieldError: player
at essentials.PluginData.(PluginData.kt:32)
at essentials.Main.(Main.kt:67)
... 12 more

Server (please complete the following information):

• OS: Ubuntu 20.04

Additional context
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