Server keep Crashing

my server keep crashing i don't know why , before it working fine but now it keep crashing

console : 

 

25.05 02:13:42 [Server] Server Shutdown Thread/INFO Saving chunks for level 'World_Survival'/the_nether 25.05 02:13:42 [Server] Server Shutdown Thread/ERROR Caught previously unhandled exception : 25.05 02:13:42 [Server] Server Shutdown Thread/ERROR java.util.concurrent.RejectedExecutionException: Task java.util.concurrent.FutureTask@2fb283ad rejected from java.util.concurrent.ThreadPoolExecutor@77eba600[Terminated, pool size = 0, active threads = 0, queued tasks = 0, completed tasks = 1612] 25.05 02:13:42 [Multicraft] Server shut down (running) 25.05 02:13:42 [Multicraft] Restarting crashed server in 10 seconds 25.05 02:13:42 [Multicraft] Server stopped 25.05 02:13:42 [Disconnect] User iiNightBlue has disconnected, reason: Server shutting down 25.05 02:13:52 [Multicraft] Loading server properties 25.05 02:13:52 [Multicraft] Starting server! 25.05 02:13:52 [Multicraft] Loaded config for "@ Custom Jar (Recommended) (Place "custom.jar" in base directory)" 25.05 02:13:53 [Multicraft] Updating eula.txt file