Bukkit

What steps will reproduce the problem ?
1. /ticket low blablabla

What is the expected output ? What do you see instead ?
Create tiket , instead i see error in tchat

What version of the product are you using ?

Forge Mod Loader version 7.10.24.1187 for Minecraft 1.7.10

What server type are you using (Spigot, CraftBukkit, ...) and what version are you using ?
Spigot

Do you have an error log (or a picture) of what happened ?

java.lang.IllegalArgumentException: No enum constant fr.skyost.tickets.Ticket.TicketPriority.low
[14:48:26] [Server thread/WARN]:     at java.lang.Enum.valueOf(Unknown Source)
[14:48:26] [Server thread/WARN]:     at fr.skyost.tickets.Ticket$TicketPriority.valueOf(Ticket.java:1)
[14:48:26] [Server thread/WARN]:     at fr.skyost.tickets.listeners.CommandsExecutor.onCommand(CommandsExecutor.java:82)
[14:48:26] [Server thread/WARN]:     at org.bukkit.command.PluginCommand.execute(PluginCommand.java:44)
[14:48:26] [Server thread/WARN]:     at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:180)
[14:48:26] [Server thread/WARN]:     at org.bukkit.craftbukkit.v1_7_R4.CraftServer.dispatchCommand(CraftServer.java:715)
[14:48:26] [Server thread/WARN]:     at net.minecraft.network.NetHandlerPlayServer.func_147361_d(NetHandlerPlayServer.java:1347)
[14:48:26] [Server thread/WARN]:     at net.minecraft.network.NetHandlerPlayServer.func_147354_a(NetHandlerPlayServer.java:1129)
[14:48:26] [Server thread/WARN]:     at net.minecraft.network.play.client.C01PacketChatMessage.func_148833_a(C01PacketChatMessage.java:38)
[14:48:26] [Server thread/WARN]:     at net.minecraft.network.play.client.C01PacketChatMessage.func_148833_a(C01PacketChatMessage.java:53)
[14:48:26] [Server thread/WARN]:     at net.minecraft.network.NetworkManager.func_74428_b(NetworkManager.java:244)
[14:48:26] [Server thread/WARN]:     at net.minecraft.network.NetworkSystem.func_151269_c(NetworkSystem.java:173)
[14:48:26] [Server thread/WARN]:     at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:990)
[14:48:26] [Server thread/WARN]:     at net.minecraft.server.dedicated.DedicatedServer.func_71190_q(DedicatedServer.java:422)
[14:48:26] [Server thread/WARN]:     at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:820)
[14:48:26] [Server thread/WARN]:     at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:680)
[14:48:26] [Server thread/WARN]:     at java.lang.Thread.run(Unknown Source)

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