Problem with my Plugin

Following Error in Console:

org.bukkit.plugin.InvalidPluginException: java.lang.UnsupportedClassVersionError: net/plugin/manager/main has been compiled by a more recent version of the Java Runtime (class file version 55.0), this version of the Java Runtime only recognizes class file versions up to 52.0
at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:139) ~[spigot.jar:git-Spigot-9de398a-9c887d4]
at org.bukkit.plugin.SimplePluginManager.loadPlugin(SimplePluginManager.java:334) ~[spigot.jar:git-Spigot-9de398a-9c887d4]
at org.bukkit.plugin.SimplePluginManager.loadPlugins(SimplePluginManager.java:253) [spigot.jar:git-Spigot-9de398a-9c887d4]
at org.bukkit.craftbukkit.v1_14_R1.CraftServer.loadPlugins(CraftServer.java:350) [spigot.jar:git-Spigot-9de398a-9c887d4]
at net.minecraft.server.v1_14_R1.DedicatedServer.init(DedicatedServer.java:194) [spigot.jar:git-Spigot-9de398a-9c887d4]
at net.minecraft.server.v1_14_R1.MinecraftServer.run(MinecraftServer.java:776) [spigot.jar:git-Spigot-9de398a-9c887d4]
at java.lang.Thread.run(Unknown Source) [?:1.8.0_231]
Caused by: java.lang.UnsupportedClassVersionError: net/plugin/manager/main has been compiled by a more recent version of the Java Runtime (class file version 55.0), this version of the Java Runtime only recognizes class file versions up to 52.0
at java.lang.ClassLoader.defineClass1(Native Method) ~[?:1.8.0_231]
at java.lang.ClassLoader.defineClass(Unknown Source) ~[?:1.8.0_231]
at java.security.SecureClassLoader.defineClass(Unknown Source) ~[?:1.8.0_231]
at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:131) ~[spigot.jar:git-Spigot-9de398a-9c887d4]
at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:81) ~[spigot.jar:git-Spigot-9de398a-9c887d4]
at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_231]
at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_231]
at java.lang.Class.forName0(Native Method) ~[?:1.8.0_231]
at java.lang.Class.forName(Unknown Source) ~[?:1.8.0_231]
at org.bukkit.plugin.java.PluginClassLoader.<init>(PluginClassLoader.java:59) ~[spigot.jar:git-Spigot-9de398a-9c887d4]
at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:135) ~[spigot.jar:git-Spigot-9de398a-9c887d4]
... 6 more

*Please help me*
Thanks